420951563408332656
420,951,563,408,332,656 is an even composite number composed of seven prime numbers multiplied together.
What does the number 420951563408332656 look like?
This visualization shows the relationship between its 7 prime factors (large circles) and 1920 divisors.
420951563408332656 is an even composite number. It is composed of seven distinct prime numbers multiplied together. It has a total of one thousand, nine hundred twenty divisors.
Prime factorization of 420951563408332656:
24 × 32 × 7 × 19 × 31 × 373 × 2413
(2 × 2 × 2 × 2 × 3 × 3 × 7 × 19 × 31 × 37 × 37 × 37 × 241 × 241 × 241)See below for interesting mathematical facts about the number 420951563408332656 from the Numbermatics database.
Names of 420951563408332656
- Cardinal: 420951563408332656 can be written as Four hundred twenty quadrillion, nine hundred fifty-one trillion, five hundred sixty-three billion, four hundred eight million, three hundred thirty-two thousand, six hundred fifty-six.
Scientific notation
- Scientific notation: 4.20951563408332656 × 1017
Factors of 420951563408332656
Divisors of 420951563408332656
- Number of divisors d(n): 1920
-
Complete list of divisors:
1 2 3 4 6 7 8 9 12 14 16 18 19 21 24 28 31 36 37 38 42 48 56 57 62 63 72 74 76 84 93 111 112 114 124 126 133 144 148 152 168 171 186 217 222 228 241 248 252 259 266 279 296 304 333 336 342 372 399 434 444 456 482 496 504 518 532 558 589 592 651 666 684 703 723 744 777 798 868 888 912 964 1008 1036 1064 1116 1147 1178 1197 1302 1332 1368 1369 1406 1446 1488 1554 1596 1687 1736 1767 1776 1928 1953 2072 2109 2128 2169 2232 2294 2331 2356 2394 2604 2664 2736 2738 2812 2892 3108 3192 3374 3441 3472 3534 3856 3906 4107 4123 4144 4218 4338 4464 4579 4588 4662 4712 4788 4921 5061 5208 5301 5328 5476 5624 5784 6216 6327 6384 6748 6882 7068 7471 7812 8029 8214 8246 8436 8676 8917 9158 9176 9324 9424 9576 9583 9842 10122 10323 10416 10602 10952 11248 11568 12321 12369 12432 12654 13496 13737 13764 14136 14763 14942 15183 15624 16058 16428 16492 16872 17352 17834 18316 18352 18648 19152 19166 19684 20244 20646 21204 21793 21904 22413 24087 24642 24738 25308 26011 26751 26992 27474 27528 28272 28749 29526 29884 30366 31248 32053 32116 32856 32984 33744 34704 35668 36632 37107 37296 38332 39368 40488 41211 41292 42408 42439 43586 44289 44826 48174 49284 49476 50616 50653 52022 52297 53502 54948 55056 57498 58081 59052 59768 60732 62419 64106 64232 65379 65712 65968 67239 71336 72261 73264 74214 76664 78033 78736 80253 80976 82422 82584 84816 84878 86247 87172 88578 89652 96159 96348 98568 98952 101232 101306 104044 104594 107004 109896 114996 116162 118104 119536 121464 124838 127317 128212 128464 130758 134478 141949 142672 144522 148428 151959 152551 153328 156066 156891 160506 164844 165168 169423 169756 172494 174243 174344 177156 179304 182077 187257 192318 192696 196137 197136 197904 202612 208088 209188 214008 219792 229992 232324 234099 236208 242928 249676 254634 256424 261516 268956 276427 283898 288477 289044 296856 297073 303918 305102 312132 313782 321012 329688 329929 338846 339512 344988 348486 348688 354312 354571 358608 364154 374514 381951 384636 385392 392274 405224 406567 416176 418376 425847 428016 455877 457653 459984 464648 468198 470673 499352 508269 509268 512848 522729 523032 537912 546231 552854 561771 567796 576954 578088 593712 594146 607836 610204 624264 627564 642024 659376 659858 677692 679024 689976 696972 708624 709142 728308 749028 763902 769272 784548 806341 810448 813134 829281 836752 851694 891219 911754 915306 929296 936396 941346 962407 989787 993643 998704 1016538 1018536 1045458 1046064 1063713 1075824 1092462 1103539 1105708 1123542 1135592 1153908 1156176 1185961 1188292 1215672 1219701 1220408 1248528 1255128 1277541 1284048 1319716 1355384 1372959 1379952 1393944 1418284 1456616 1498056 1524807 1527804 1538544 1569096 1570243 1612682 1626268 1638693 1658562 1703388 1782438 1800511 1823508 1830612 1872792 1882692 1924814 1934989 1979574 1987286 2033076 2037072 2090916 2127426 2148997 2184924 2207078 2211416 2247084 2271184 2307816 2309503 2371922 2376584 2419023 2431344 2439402 2440816 2487843 2510256 2555082 2639432 2673657 2710768 2745918 2787888 2836568 2887221 2913232 2969361 2980929 2996112 3049614 3055608 3138192 3140486 3191139 3225364 3252536 3277386 3310617 3317124 3406776 3557883 3564876 3601022 3647016 3659103 3661224 3745584 3765384 3849628 3869978 3959148 3974572 4066152 4181832 4254852 4297994 4369848 4414156 4422832 4494168 4615632 4619006 4710729 4743844 4753168 4838046 4878804 4975686 5110164 5252113 5278864 5347314 5401533 5491836 5644387 5673136 5774442 5804967 5938722 5961858 6099228 6111216 6268651 6280972 6382278 6446991 6450728 6505072 6554772 6621234 6634248 6736849 6813552 6928509 7115766 7129752 7202044 7257069 7294032 7318206 7322448 7530768 7699256 7724773 7739956 7918296 7949144 8132304 8363664 8509704 8595988 8661663 8739696 8828312 8942787 8988336 9238012 9421458 9487688 9676092 9757608 9931851 9951372 10220328 10227799 10504226 10673649 10694628 10803066 10983672 10991701 11288774 11548884 11609934 11877444 11923716 12198456 12207373 12537302 12561944 12603577 12764556 12893982 12901456 13109544 13242468 13268496 13473698 13857018 13997521 14132187 14231532 14259504 14404088 14514138 14636412 15042979 15398512 15449546 15479912 15756339 15836592 15898288 16204599 16933161 17019408 17191976 17323326 17414901 17656624 17885574 18476024 18805953 18842916 18975376 19340973 19352184 19515216 19863702 19902744 20210547 20440656 20455598 20785527 21008452 21347298 21389256 21606132 21967344 21983402 22577548 23097768 23174319 23219868 23754888 23847432 24396912 24414746 25074604 25123888 25207154 25529112 25787964 26219088 26484936 26947396 27714036 27995042 28264374 28463064 28808176 29028276 29272824 29834617 30085958 30683397 30899092 30959824 31512678 32409198 32975103 33866322 34209709 34383952 34646652 34829802 35771148 36622119 36764791 36952048 37611906 37685832 37810731 38681946 38704368 39727404 39805488 40421094 40830943 40911196 41571054 41992563 42016904 42694596 42778512 43212264 43880557 43966804 45128937 45155096 46195536 46348638 46439736 47269017 47509776 47694864 48829492 50149208 50414308 50799483 51058224 51575928 52969872 53894792 55428072 55990084 56417859 56528748 56926128 58056552 58545648 59669234 60171916 60631641 61366794 61798184 63025356 64818396 65950206 66618907 67732644 68419418 69293304 69522957 69659604 71542296 71594593 73244238 73529582 75223812 75371664 75621462 77363892 79454808 79512889 80842188 81661886 81822392 83142108 83985126 84033808 85389192 85451611 86424528 87761114 87933608 89503851 90257874 90310192 92050191 92697276 92879472 94538034 97658984 97982647 98925309 100298416 100828616 101598966 102629127 103151856 107789584 109866357 110294373 110856144 111980168 112835718 113057496 113432193 116113104 119338468 120343832 121263282 122492829 122733588 123596368 125977689 126050712 129636792 131641671 131900412 133237814 135386811 135465288 136838836 138586608 139045914 139319208 143084592 143189186 146488476 147059164 150447624 151242924 154727784 158909616 159025778 161684376 163323772 163644784 166284216 167970252 170778384 170903222 175522228 175867216 179007702 180515748 184100382 185394552 189076068 194328181 195317968 195965294 197850618 199856721 201657232 203197932 205258254 208842319 214783779 219732714 220588746 223960336 225671436 226114992 226864386 231940087 238538667 238676936 239467963 240687664 242526564 244985658 245467176 251955378 252101424 256354833 259273584 263283342 263800824 265952899 266475628 268511553 270773622 270930576 273677672 278091828 278638416 285816601 286378372 292976952 293947941 294118328 300895248 302485848 307887381 309455568 318051556 323368752 326647544 330883119 332568432 335940504 341806444 351044456 358015404 361031496 367478487 368200764 370789104 378152136 378428563 388656362 391930588 394925013 395701236 399713442 406395864 410516508 417684638 429567558 433923151 439465428 441177492 451342872 453728772 463880174 466332349 477077334 477353872 478935926 485053128 489971316 490934352 503910756 512709666 517908277 526566684 527601648 531905798 532951256 537023106 541547244 547355344 556183656 556590223 571633202 572756744 582984543 585953904 587895882 588236656 599570163 604971696 615774762 626526957 636103112 644351337 653295088 661766238 671881008 683612888 695820261 702088912 715616001 716030808 718403889 722062992 734956974 736401528 756304272 756857126 769064499 777312724 783861176 789850026 791402472 797858697 799426884 812791728 821033016 835369276 857449803 859135116 867846302 878930856 881843823 882354984 902685744 907457544 927760348 932664698 954154668 957871852 970106256 979942632 1007821512 1025419332 1035816554 1053133368 1063811596 1065902512 1074046212 1083094488 1112367312 1113180446 1135285689 1143266404 1145513488 1165969086 1175791764 1199140326 1231549524 1253053914 1265759233 1272206224 1288702674 1301769453 1323532476 1360297267 1367225776 1391640522 1398997047 1431232002 1432061616 1436807778 1469913948 1472803056 1510744891 1513714252 1538128998 1553724831 1554625448 1567722352 1579700052 1582804944 1595717394 1598853768 1623580609 1642066032 1669770669 1670738552 1714899606 1718270232 1735692604 1748953629 1757861712 1763687646 1764709968 1814915088 1855520696 1861670293 1865329396 1879580871 1908309336 1915743704 1959885264 2015643024 2050838664 2071633108 2087460783 2106266736 2127623192 2148092424 2155211667 2166188976 2226360892 2270571378 2286532808 2331938172 2351583528 2393576091 2398280652 2463099048 2464899559 2506107828 2531518466 2572349409 2577405348 2603538906 2647064952 2648999941 2720594534 2783281044 2797994094 2862464004 2873615556 2939827896 2941976893 3021489782 3027428504 3037462057 3076257996 3107449662 3109250896 3159400104 3191434788 3197707536 3247161218 3339541338 3341477104 3405857067 3429799212 3436540464 3471385208 3497907258 3527375292 3625357939 3711041392 3723340586 3730658792 3759161742 3797277699 3816618672 3831487408 3905308359 4080891801 4101677328 4143266216 4174921566 4196991141 4255246384 4296184848 4310423334 4452721784 4532234673 4541142756 4573065616 4661174493 4663876344 4703167056 4787152182 4796561304 4870741827 4926198096 4929799118 5009312007 5012215656 5063036932 5144698818 5154810696 5207077812 5294129904 5297999882 5441189068 5566562088 5585010879 5595988188 5724928008 5747231112 5879655792 5883953786 6042979564 6054857008 6074924114 6152515992 6214899324 6318800208 6382869576 6494322436 6679082676 6811714134 6859598424 6942770416 6995814516 7054750584 7190142697 7250715878 7394698677 7446681172 7461317584 7518323484 7594555398 7810616718 7946999823 8161783602 8244539869 8286532432 8349843132 8393982282 8620846668 8825930679 8860314631 8905443568 9064469346 9082285512 9112386171 9322348986 9327752688 9574304364 9593122608 9741483654 9840257263 9859598236 10018624014 10024431312 10126073864 10289397636 10309621392 10414155624 10575214237 10595999764 10876073817 10882378136 11133124176 11170021758 11191976376 11391833097 11449856016 11494462224 11767907572 12085959128 12149848228 12242675403 12305031984 12429798648 12765739152 12988644872 13358165352 13596704019 13623428268 13719196848 13991629032 14109501168 14380285394 14501431756 14612225481 14789397354 14893362344 15036646968 15189110796 15621233436 15893999646 16055156587 16323567204 16489079738 16699686264 16755032637 16787964564 17241693336 17254296913 17651861358 17720629262 18128938692 18164571024 18224772342 18644697972 19148608728 19162606249 19482967308 19680514526 19719196472 20037248028 20252147728 20578795272 20593838251 20828311248 21150428474 21191999528 21570428091 21752147634 21764756272 22184096031 22340043516 22383952752 22783666194 23535815144 23840999469 24171918256 24299696456 24485350806 24733619607 24859597296 25977289744 26477792037 26580943893 26716330704 27193408038 27246856536 27337158513 27983258064 28760570788 29002863512 29224450962 29520771789 29578794708 29786724688 30073293936 30378221592 31242466872 31725642711 31787999292 32110313174 32628221451 32647134408 32978159476 33399372528 33510065274 33575929128 34483386672 34508593826 35303722716 35441258524 36257877384 36449544684 37289395944 38297217456 38325212498 38965934616 39361029052 39438392944 40074496056 41157590544 41187676502 42300856948 42383999056 43140856182 43504295268 44368192062 44680087032 45567332388 46833091621 47071630288 47681998938 48165469761 48599392912 48970701612 49467239214 50330998879 51762890739 52955584074 53161887786 54386816076 54493713072 54674317026 55897560967 57487818747 57521141576 57711779083 58005727024 58448901924 59041543578 59157589416 60756443184 61781514753 62484933744 63451285422 63575998584 64220626348 64711284273 65256442902 65294268816 65956318952 67020130548 67151858256 68881800841 69017187652 70607445432 70882517048 72515754768 72899089368 74200858821 74578791888 76650424996 77931869232 78722058104 79742831679 80148992112 82375353004 84601713896 86281712364 87008590536 88562315367 88736384124 89360174064 91134664776 91201283683 93666183242 95176928133 95363997876 96330939522 97941403224 98934478428 100661997758 103525781478 105911168148 106323775572 108773632152 109348634052 111795121934 112386096109 114975637494 115042283152 115423558166 116897803848 118083087156 118315178832 123563029506 126902570844 127151997168 128441252696 129422568546 130512885804 131912637904 134040261096 134138243743 137763601682 138034375304 140499274863 141214890864 141765034096 144496409283 145798178736 148401717642 150992996637 153300849992 155288672217 157444116208 159485663358 164750706008 167692682901 169203427792 172463456241 172563424728 173135337249 174017181072 177124630734 177472768248 182269329552 182402567366 185344544259 187332366484 190353856266 190727995752 192661879044 195882806448 197868956856 201323995516 206645402523 207051562956 211822336296 212647551144 217547264304 218697268104 223590243868 224772192218 229951274988 230847116332 233795607696 236166174312 247126059012 253805141688 256882505392 258845137092 261025771608 268080522192 268276487486 273603851049 275527203364 276068750608 280998549726 288992818566 296803435284 301985993274 305047975153 306601699984 310577344434 318971326716 327831641347 329501412016 335385365802 337158288327 344926912482 345126849456 346270674498 354249261468 354945536496 364089518731 364805134732 370689088518 374664732968 380707712532 381455991504 385323758088 391282926769 395737913712 402414731229 402647991032 413290805046 414103125912 421497824589 423644672592 425295102288 437394536208 447180487736 449544384436 452978989911 459902549976 461694232664 472332348624 494252118024 503078048703 507610283376 517690274184 519406011747 522051543216 536552974972 547207702098 551054406728 561997099452 577985637132 593606870568 594040793719 603971986548 610095950306 619936207569 621154688868 637942653432 638408985781 655663282694 670770731604 674316576654 689853824964 692541348996 708498522936 709016431213 728179037462 729610269464 741378177036 749329465936 761415425064 770647516176 782565853538 804829462458 805295982064 820811553147 826581610092 828206251824 842995649178 894360975472 899088768872 905957979822 915143925459 919805099952 923388465328 983494924041 988504236048 1006156097406 1011474864981 1035380548368 1038812023494 1073105949944 1092268556193 1094415404196 1102108813456 1123994198904 1155971274264 1173848780307 1187213741136 1188081587438 1207244193687 1207943973096 1220191900612 1239872415138 1242309377736 1275885306864 1276817971562 1311326565388 1341541463208 1348633153308 1379707649928 1385082697992 1416997045872 1418032862426 1456358074924 1459220538928 1482756354072 1522830850128 1565131707076 1609658924916 1641623106294 1653163220184 1685991298356 1732824389977 1782122381157 1798177537744 1811915959644 1830287850918 1915226957343 1966989848082 2012312194812 2022949729962 2077624046988 2127049293639 2135335826071 2146211899888 2184537112386 2188830808392 2247988397808 2311942548528 2347697560614 2376163174876 2414488387374 2415887946192 2440383801224 2479744830276 2484618755472 2548626631117 2553635943124 2622653130776 2683082926416 2697266306616 2745431776377 2759415299856 2770165395984 2836065724852 2912716149848 2950484772123 2965512708144 3130263414152 3219317849832 3276805668579 3283246212588 3306326440368 3371982596712 3465648779954 3521546340921 3564244762314 3623831919288 3660575701836 3830453914686 3933979696164 4024624389624 4045899459924 4155248093976 4158285556033 4254098587278 4270671652142 4369074224772 4377661616784 4695395121228 4752326349752 4828976774748 4880767602448 4959489660552 4963115018491 5097253262234 5107271886248 5198473169931 5245306261552 5346367143471 5394532613232 5490863552754 5672131449704 5745680872029 5825432299696 5900969544246 6260526828304 6381147880917 6406007478213 6438635699664 6553611337158 6566492425176 6743965193424 6931297559908 7043092681842 7128489524628 7247663838576 7321151403672 7645879893351 7660907829372 7867959392328 8049248779248 8091798919848 8310496187952 8316571112066 8508197174556 8541343304284 8738148449544 9390790242456 9504652699504 9657953549496 9918979321104 9926230036982 10194506524468 10214543772496 10396946339862 10692734286942 10981727105508 11286775080661 11344262899408 11491361744058 11801939088492 12129770729839 12474856668099 12762295761834 12812014956426 13107222674316 13132984850352 13471312193047 13862595119816 14086185363684 14256979049256 14642302807344 14889345055473 15291759786702 15321815658744 15595419509793 15735918784656 16183597839696 16633142224132 17016394349112 17082686608568 17476296899088 18781580484912 19218022434639 19315907098992 19852460073964 20389013048936 20793892679724 21385468573884 21963454211016 21979509367603 22573550161322 22937639680053 22982723488116 23603878176984 24259541459678 24949713336198 25524591523668 25624029912852 26214445348632 26942624386094 27725190239632 28172370727368 28513958098512 29778690110946 30583519573404 30643631317488 31190839019586 33266284448264 33860325241983 34032788698224 34165373217136 36389312189517 37424570004297 38436044869278 39704920147928 40413936579141 40778026097872 41587785359448 42770937147768 43926908422032 43959018735206 44668035166419 45147100322644 45875279360106 45965446976232 47207756353968 48519082919356 49899426672396 51049183047336 51248059825704 52428890697264 53885248772188 56344741454736 59557380221892 61167039146808 62381678039172 65938528102809 66532568896528 67720650483966 72778624379034 74849140008594 76872089738556 79007425564627 79409840295856 80827873158282 83175570718896 85541874295536 87918037470412 89336070332838 90294200645288 91750558720212 91930893952464 94299185351329 97038165838712 99798853344792 101580975725949 102098366094672 102496119651408 107770497544376 109167936568551 119114760443784 121241809737423 122334078293616 124763356078344 131877056205618 135441300967932 145557248758068 149698280017188 153744179477112 153856565573221 158014851129254 161655746316564 175836074940824 178672140665676 180588401290576 183501117440424 188598370702658 194076331677424 197815584308427 199597706689584 203161951451898 215540995088752 218335873137102 237022276693881 238229520887568 242483619474846 249526712156688 263754112411236 270882601935864 282897556053987 291114497516136 299396560034376 307488358954224 307713131146442 316029702258508 323311492633128 351672149881648 357344281331352 367002234880848 377196741405316 395631168616854 406323902903796 417610677984457 436671746274204 461569696719663 474044553387762 484967238949692 527508224822472 541765203871728 565795112107974 582228995032272 598793120068752 615426262292884 632059404517016 646622985266256 711066830081643 714688562662704 754393482810632 791262337233708 812647805807592 835221355968914 848692668161961 873343492548408 923139393439326 948089106775524 969934477899384 1055016449644944 1131590224215948 1230852524585768 1252832033953371 1264118809034032 1384709090158989 1422133660163286 1508786965621264 1582524674467416 1625295611615184 1670442711937828 1697385336323922 1746686985096816 1846278786878652 1896178213551048 1939868955798768 2263180448431896 2461705049171536 2505664067906742 2769418180317978 2844267320326572 2923274745891199 3165049348934832 3340885423875656 3394770672647844 3692557573757304 3758496101860113 3792356427102096 4526360896863792 5011328135813484 5538836360635956 5688534640653144 5846549491782398 6681770847751312 6789541345295688 7385115147514608 7516992203720226 8769824237673597 10022656271626968 11077672721271912 11377069281306288 11693098983564796 13579082690591376 15033984407440452 17539648475347194 20045312543253936 22155345442543824 23386197967129592 26309472713020791 30067968814880904 35079296950694388 46772395934259184 52618945426041582 60135937629761808 70158593901388776 105237890852083164 140317187802777552 210475781704166328 420951563408332656
- Sum of all divisors σ(n): 1509857982320230400
- Sum of proper divisors (its aliquot sum) s(n): 1088906418911897744
- 420951563408332656 is an abundant number, because the sum of its proper divisors (1088906418911897744) is greater than itself. Its abundance is 667954855503565088
Bases of 420951563408332656
- Binary: 101110101111000010100110111011101001001100101010111011100002
- Hexadecimal: 0x5D7853774995770
- Base-36: 374UVIJY1A40
Squares and roots of 420951563408332656
- 420951563408332656 squared (4209515634083326562) is 177200218735919508701018213956014336
- 420951563408332656 cubed (4209515634083326563) is 74592709113183837390104692446354525198642768992956416
-
The
square root of 420951563408332656 is 648807801.5933013239 -
The
cube root of 420951563408332656 is 749452.3785610475
Scales and comparisons
How big is 420951563408332656?- 420,951,563,408,332,656 seconds is equal to 13,384,957,627 years, 36 weeks, 5 days, 7 hours, 57 minutes, 36 seconds.
-
To count from 1 to 420,951,563,408,332,656 would take you about forty billion, one hundred fifty-four million, eight hundred seventy-two thousand, eight hundred eighty-three years!
This is a very rough estimate, based on a speaking rate of half a second every third order of magnitude. If you speak quickly, you could probably say any randomly-chosen number between one and a thousand in around half a second. Very big numbers obviously take longer to say, so we add half a second for every extra x1000. (We do not count involuntary pauses, bathroom breaks or the necessity of sleep in our calculation!)
- A cube with a volume of 420951563408332656 cubic inches would be around 62454.4 feet tall.
Recreational maths with 420951563408332656
- 420951563408332656 backwards is 656233804365159024
- 420951563408332656 is a
Harshad number . - The number of decimal digits it has is: 18
- The sum of 420951563408332656's digits is 72
- More coming soon!
Link to this page
HTML: To link to this page, just copy and paste the link below into your blog, web page or email.
BBCODE: To link to this page in a forum post or comment box, just copy and paste the link code below:
Cite this page
MLA style:
"Number 420951563408332656 - Facts about the integer". Numbermatics.com. 2024. Web. 11 May 2024.
APA style:
Numbermatics. (2024). Number 420951563408332656 - Facts about the integer. Retrieved 11 May 2024, from https://numbermatics.com/n/420951563408332656/
Chicago style:
Numbermatics. 2024. "Number 420951563408332656 - Facts about the integer". https://numbermatics.com/n/420951563408332656/
The information we have on file for 420951563408332656 includes mathematical data and numerical statistics calculated using standard algorithms and methods. We are adding more all the time. If there are any features you would like to see, please contact us. Information provided for educational use, intellectual curiosity and fun!
Keywords: Divisors of 420951563408332656, math, Factors of 420951563408332656, curriculum, school, college, exams, university, Prime factorization of 420951563408332656, STEM, science, technology, engineering, physics, economics, calculator, four hundred twenty quadrillion, nine hundred fifty-one trillion, five hundred sixty-three billion, four hundred eight million, three hundred thirty-two thousand, six hundred fifty-six.