30931718432160
30,931,718,432,160 is an even composite number composed of seven prime numbers multiplied together.
What does the number 30931718432160 look like?
This visualization shows the relationship between its 7 prime factors (large circles) and 2304 divisors.
30931718432160 is an even composite number. It is composed of seven distinct prime numbers multiplied together. It has a total of two thousand, three hundred four divisors.
Prime factorization of 30931718432160:
25 × 3 × 5 × 75 × 13 × 193 × 43
(2 × 2 × 2 × 2 × 2 × 3 × 5 × 7 × 7 × 7 × 7 × 7 × 13 × 19 × 19 × 19 × 43)See below for interesting mathematical facts about the number 30931718432160 from the Numbermatics database.
Names of 30931718432160
- Cardinal: 30931718432160 can be written as Thirty trillion, nine hundred thirty-one billion, seven hundred eighteen million, four hundred thirty-two thousand, one hundred sixty.
Scientific notation
- Scientific notation: 3.093171843216 × 1013
Factors of 30931718432160
Divisors of 30931718432160
- Number of divisors d(n): 2304
-
Complete list of divisors:
1 2 3 4 5 6 7 8 10 12 13 14 15 16 19 20 21 24 26 28 30 32 35 38 39 40 42 43 48 49 52 56 57 60 65 70 76 78 80 84 86 91 95 96 98 104 105 112 114 120 129 130 133 140 147 152 156 160 168 172 182 190 195 196 208 210 215 224 228 240 245 247 258 260 266 273 280 285 294 301 304 312 336 343 344 361 364 380 390 392 399 416 420 430 455 456 480 490 494 516 520 532 546 559 560 570 588 602 608 624 637 645 665 672 686 688 722 728 735 741 760 780 784 798 817 840 860 903 910 912 931 980 988 1029 1032 1040 1064 1083 1092 1118 1120 1140 1176 1204 1235 1248 1274 1290 1330 1365 1372 1376 1444 1456 1470 1482 1505 1520 1560 1568 1596 1634 1677 1680 1715 1720 1729 1805 1806 1820 1824 1862 1911 1960 1976 1995 2058 2064 2080 2107 2128 2166 2184 2236 2280 2352 2401 2408 2451 2470 2527 2548 2580 2660 2730 2744 2793 2795 2888 2912 2940 2964 3010 3040 3120 3185 3192 3268 3354 3360 3430 3440 3458 3610 3612 3640 3705 3724 3822 3913 3920 3952 3990 4085 4116 4128 4214 4256 4332 4368 4459 4472 4515 4560 4655 4693 4704 4802 4816 4902 4940 5054 5096 5145 5160 5187 5320 5415 5460 5488 5586 5590 5719 5776 5880 5928 6020 6240 6321 6370 6384 6517 6536 6708 6859 6860 6880 6916 7203 7220 7224 7280 7410 7448 7581 7644 7826 7840 7904 7980 8170 8232 8385 8428 8645 8664 8736 8918 8944 9030 9120 9310 9386 9555 9604 9632 9804 9880 10108 10192 10290 10320 10374 10535 10621 10640 10830 10920 10976 11172 11180 11438 11552 11739 11760 11856 12005 12040 12103 12255 12635 12642 12740 12768 13034 13072 13377 13416 13718 13720 13832 13965 14079 14406 14440 14448 14560 14749 14820 14896 15162 15288 15523 15652 15960 16340 16464 16770 16807 16856 17157 17290 17328 17689 17836 17888 18060 18620 18772 19110 19208 19551 19565 19608 19760 20216 20384 20577 20580 20640 20748 21070 21242 21280 21660 21840 22295 22344 22360 22876 23465 23478 23520 23712 24010 24080 24206 24510 25270 25284 25480 25935 26068 26144 26754 26832 27391 27436 27440 27664 27930 28158 28595 28812 28880 28896 29498 29640 29792 30324 30576 31046 31213 31304 31605 31863 31920 32585 32680 32851 32928 33540 33614 33712 34295 34314 34580 34656 35378 35672 36015 36120 36309 37240 37544 37905 38220 38416 39102 39130 39216 39520 40033 40432 41154 41160 41496 42140 42484 43320 43680 44247 44590 44688 44720 45619 45752 46569 46930 46956 48013 48020 48160 48412 49020 50421 50540 50568 50960 51870 52136 53067 53105 53508 53664 54782 54872 54880 55328 55860 56316 57190 57624 57760 58695 58996 59280 60515 60648 61152 62092 62426 62608 63210 63726 63840 65170 65360 65702 66885 67080 67228 67424 68590 68628 69160 70395 70756 71344 72030 72240 72618 73745 74347 74480 75088 75810 76440 76832 77615 78204 78260 78432 80066 80864 82173 82308 82320 82992 84035 84280 84721 84968 85785 86640 88445 88494 89167 89180 89376 89440 91238 91504 93138 93639 93860 93912 96026 96040 96824 97755 98040 98553 100842 101080 101136 101920 102885 103243 103740 104272 106134 106210 107016 108661 109564 109744 111720 112632 114380 115248 117390 117992 118560 120099 121030 121296 123823 124184 124852 125216 126420 127452 130340 130720 131404 133770 134160 134456 136857 136955 137180 137256 138320 140790 141512 142688 144039 144060 144480 145236 147490 148694 148960 150176 151620 152880 155230 156065 156408 156520 159315 160132 164255 164346 164616 164640 165984 168070 168560 169442 169936 171570 173280 176890 176988 178334 178360 181545 182476 183008 186276 187278 187720 187824 191737 192052 192080 193648 195510 196080 197106 200165 201684 201799 202160 202272 205770 206486 207480 208544 212268 212420 214032 217322 218491 219128 219488 221235 223041 223440 225264 228095 228760 229957 230496 232845 234780 235984 240065 240198 242060 242592 247646 248368 249704 252105 252840 254163 254904 260680 262808 265335 267501 267540 268320 268912 273714 273910 274360 274512 276640 280231 281580 283024 288078 288120 290472 294937 294980 297388 303240 305760 309729 310460 312130 312816 313040 318630 319333 320264 325983 328510 328692 329232 336091 336140 337120 338884 339872 343140 353780 353976 356668 356720 363090 364952 371469 371735 372552 374556 375440 375648 383474 384104 384160 387296 391020 392160 394212 400330 403368 403598 404320 410865 411540 412972 414960 423605 424536 424840 428064 434644 436982 438256 442470 445835 446082 446880 450528 456190 457520 459914 465690 468195 469560 471968 480130 480396 484120 492765 495292 496736 499408 504210 505680 508326 509808 516215 520429 521360 525616 530670 535002 535080 537824 543305 547428 547820 548720 549024 560462 563160 566048 575211 576156 576240 580944 589874 589960 593047 594776 600495 605397 606480 619115 619458 620920 624169 624260 625632 626080 637260 638666 640528 651966 655473 657020 657384 658464 672182 672280 677768 684285 686280 689871 707560 707952 713336 713440 720195 722701 726180 729904 742938 743470 745104 749112 750880 760627 766948 768208 782040 788424 800660 806736 807196 821730 823080 825944 829920 840693 847210 849072 849680 866761 869288 873964 876512 884811 884940 891670 892164 912380 915040 919828 931380 936390 939120 957999 958685 960260 960792 968240 985530 990584 998816 1008273 1008420 1008995 1011360 1016652 1019616 1032430 1040858 1042720 1051232 1061340 1070004 1070160 1086610 1092455 1094856 1095640 1097440 1115205 1120924 1126320 1149785 1150422 1152312 1152480 1161888 1179748 1179920 1186094 1189552 1200990 1210794 1212960 1238230 1238916 1241840 1248338 1248520 1270815 1274520 1277332 1281056 1303932 1310946 1314040 1314768 1337505 1342159 1344364 1344560 1355536 1368570 1372560 1379742 1401155 1412593 1415120 1415904 1426672 1440390 1445402 1452360 1459808 1474685 1485876 1486940 1490208 1498224 1521254 1533896 1536416 1548645 1561287 1564080 1576848 1596665 1601320 1609699 1613472 1614392 1629915 1643460 1646160 1651888 1680455 1681386 1694420 1698144 1699360 1733522 1738576 1747928 1769622 1769880 1779141 1783340 1784328 1824760 1839656 1857345 1862760 1872507 1872780 1878240 1915998 1917370 1920520 1921584 1936480 1961617 1971060 1981168 2016546 2016840 2017990 2033304 2064559 2064860 2081716 2122680 2140008 2140320 2168103 2173220 2184910 2189712 2191280 2230410 2241848 2252640 2281881 2299570 2300844 2304624 2352637 2359496 2359840 2372188 2379104 2401980 2421588 2476460 2477832 2483680 2496676 2497040 2541630 2549040 2554664 2600283 2602145 2607864 2621892 2628080 2629536 2675010 2684318 2688728 2689120 2711072 2737140 2745120 2759484 2802310 2825186 2830240 2853344 2876055 2880780 2890804 2904720 2949370 2965235 2971752 2973880 2996448 3026985 3042508 3067792 3097290 3120845 3122574 3128160 3153696 3193330 3202640 3219398 3228784 3259830 3277365 3286920 3292320 3303776 3360910 3362772 3388840 3449355 3467044 3477152 3495856 3539244 3539760 3558282 3566680 3568656 3613505 3643003 3649520 3679312 3714690 3725520 3745014 3745560 3803135 3831996 3834181 3834740 3841040 3843168 3923234 3942120 3962336 4026477 4033092 4033680 4035980 4066608 4129118 4129720 4151329 4163432 4203465 4237779 4245360 4280016 4333805 4336206 4346440 4369183 4369820 4379424 4382560 4424055 4460820 4483696 4563762 4599140 4601688 4609248 4705274 4718992 4744376 4789995 4803960 4829097 4843176 4952920 4955664 4993352 4994080 5041365 5083260 5098080 5109328 5200566 5204290 5215728 5243784 5256160 5324389 5350020 5368636 5377456 5474280 5518968 5604620 5650372 5752110 5761560 5781608 5809440 5884851 5898740 5930470 5943504 5947760 6053970 6067327 6085016 6135584 6193677 6194580 6241690 6245148 6386660 6405280 6438796 6457568 6519660 6554730 6573840 6710795 6721820 6725544 6777680 6898710 6934088 6991712 7057911 7062965 7078488 7079520 7116564 7133360 7137312 7227010 7286006 7299040 7358624 7429380 7451040 7490028 7491120 7606270 7663992 7668362 7669480 7682080 7806435 7846468 7884240 8048495 8052954 8066184 8067360 8071960 8133216 8258236 8259440 8302658 8326864 8406930 8475558 8490720 8560032 8667610 8672412 8692880 8738366 8739640 8848110 8895705 8921640 8967392 9127524 9198280 9203376 9362535 9395113 9410548 9437984 9488752 9579990 9607920 9658194 9686352 9808085 9888151 9905840 9911328 9986704 10082730 10166520 10218656 10322795 10401132 10408580 10431456 10487568 10648778 10700040 10737272 10754912 10840515 10929009 10948560 11037936 11209240 11267893 11300744 11409405 11502543 11504220 11523120 11563216 11763185 11769702 11797480 11860940 11887008 11895520 12107940 12134654 12170032 12387354 12389160 12453987 12483380 12490296 12773320 12877592 13001415 13039320 13107549 13109460 13147680 13421590 13443640 13451088 13555360 13731319 13797420 13868176 14115822 14125930 14156976 14233128 14266720 14451913 14454020 14572012 14858760 14980056 14982240 15212540 15327984 15336724 15338960 15612870 15692936 15768480 15973167 16096990 16105908 16132368 16143920 16468459 16516472 16518880 16605316 16653728 16813860 16951116 17335220 17344824 17385760 17476732 17479280 17696220 17791410 17843280 18201981 18215015 18255048 18396560 18406752 18725070 18790226 18821096 18977504 19159980 19170905 19215840 19316388 19372704 19616170 19776302 19811680 19973408 20132385 20165460 20333040 20645590 20756645 20802264 20817160 20975136 21188895 21297556 21400080 21474544 21681030 21845915 21858018 21897120 22075872 22418480 22535786 22601488 22818810 23005086 23008440 23046240 23126432 23526370 23539404 23594960 23721880 24145485 24215880 24269308 24340064 24774708 24778320 24907974 24966760 24980592 25501021 25546640 25755184 26002830 26078640 26215098 26218920 26621945 26839267 26843180 26887280 26902176 27462638 27594840 27736352 28185339 28231644 28251860 28313952 28466256 28903826 28908040 29144024 29424255 29664453 29717520 29960112 30336635 30425080 30584281 30655968 30673448 30677920 30968385 31225740 31385872 31946334 32193980 32211816 32264736 32287840 32936918 33032944 33210632 33627720 33803679 33902232 34670440 34689648 34953464 34958560 35289555 35392440 35582820 35686560 36403962 36430030 36510096 36793120 37270723 37450140 37580452 37642192 38319960 38341810 38632776 39232340 39552604 40264770 40330920 40666080 41193957 41291180 41513290 41604528 41634320 42377790 42595112 42800160 42949088 43355739 43362060 43691830 43716036 44836960 45071572 45202976 45637620 46010172 46016880 46975565 47052740 47078808 47189920 47443760 48290970 48431760 48538616 49405377 49440755 49549416 49556640 49815948 49933520 49961184 51002042 51093280 51510368 52005660 52157280 52430196 52437840 53243890 53678534 53686360 53774560 54645045 54925276 55189680 56339465 56370678 56463288 56503720 56932512 57512715 57807652 57816080 58288048 58848510 59328906 59435040 59920224 60673270 60850160 61168562 61346896 61936770 62269935 62451480 62771744 63892668 64387960 64423632 65537745 65873836 66065888 66421264 67255440 67607358 67804464 68656595 69217057 69340880 69379296 69906928 70579110 70784880 71165640 72259565 72807924 72860060 73020192 74541446 74900280 75160904 75284384 76503063 76639920 76683620 77265552 78464680 78875251 79105208 79865835 80517801 80529540 80661840 82342295 82387914 82582360 83026580 83209056 83268640 84755580 85190224 86711478 86724120 87383660 87432072 90143144 91009905 91275240 91752843 92020344 92033760 93951130 94105480 94157616 94887520 96581940 96863520 97077232 98810754 98881510 99098832 99631896 99867040 101163391 102004084 104011320 104860392 104875680 106487780 107357068 107372720 109290090 109850552 110379360 111812169 112678930 112741356 112926576 113007440 115025430 115279213 115615304 115632160 116576096 117697020 118657812 121346540 121700320 122337124 122693792 123873540 124539870 124902960 127505105 127785336 128775920 128847264 131075490 131747672 132842528 134196335 134510880 135214716 135608928 137313190 138434114 138681760 139813856 140926695 141158220 141569760 142331280 144519130 145615848 145720120 148322265 149082892 149800560 150321808 152921405 153006126 153279840 153367240 154531104 156929360 157750502 158210416 159731670 161035602 161059080 161323680 164684590 164775828 165164720 166053160 169018395 169511160 170380448 173422956 173448240 174767320 174864144 178507147 180286288 182019810 182550480 183505686 184040688 186353615 187874869 187902260 188210960 188315232 193163880 194154464 197621508 197763020 198197664 199263792 202326782 204008168 205969785 207651171 208022640 209720784 212975560 214089967 214714136 214745440 216778695 218580180 219701104 223624338 225357860 225482712 225853152 226014880 230050860 230558426 231230608 235394040 236625753 237315624 242693080 244674248 247026885 247747080 249079740 249805920 255010210 255570672 257551840 260895061 262150980 263495344 268392670 270429432 274626380 276868228 281853390 282316440 284662560 289038260 291231696 291440240 296644530 298165784 299601120 300643616 303490173 305842810 306012252 306734480 313858720 315501004 316420832 319463340 322071204 322118160 329369180 329551656 330329440 332106320 338036790 339022320 345837639 346085285 346845912 346896480 349534640 349728288 357014294 360572576 364039620 365100960 367011372 368081376 372707230 375749738 375804520 376421920 382515315 386327760 394376255 395243016 395526040 398527584 402589005 404653564 408016336 411939570 415302342 416045280 419441568 425951120 428179934 429428272 433557390 437160360 439402208 447248676 450715720 450965424 458764215 460101720 461116852 462461216 470788080 473251506 474631248 484519399 485386160 489348496 494053770 495494160 498159480 505816955 510020420 511141344 521790122 524301960 526990688 535521441 536785340 540858864 549252760 553736456 559060845 563624607 563706780 564632880 576396065 578076520 582463392 582880480 593289060 596331568 606980346 611685620 612024504 613468960 631002008 638926680 642269901 644142408 644236320 658738360 659103312 664212640 676073580 678044640 691675278 692170570 693691824 699069280 708143737 714028588 728079240 734022744 745414460 751499476 751609040 765030630 772655520 782685183 788752510 790486032 791052080 805178010 809307128 816032672 823879140 830604684 851902240 856359868 858856544 867114780 874320720 892535735 894497352 901431440 901930848 917528430 920203440 922233704 939374345 941576160 946503012 949262496 969038798 970772320 978696992 988107540 990988320 996318960 1011633910 1020040840 1038255855 1043580244 1048603920 1070449835 1071042882 1073570680 1081717728 1098505520 1107472912 1118121690 1127249214 1127413560 1129265760 1152792130 1156153040 1183128765 1186578120 1192663136 1213960692 1223371240 1224049008 1262004016 1277853360 1284539802 1288284816 1304475305 1315124083 1317476720 1318206624 1352147160 1383350556 1384341140 1387383648 1416287474 1428057176 1453558197 1456158480 1468045488 1490828920 1498629769 1502998952 1503218080 1517450865 1530061260 1565370366 1577505020 1580972064 1582104160 1610356020 1618614256 1647758280 1661209368 1712719736 1729188195 1734229560 1748641440 1785071470 1788994704 1802862880 1835056860 1840406880 1844467408 1878748690 1893006024 1938077596 1976215080 1992637920 2023267820 2040081680 2076511710 2087160488 2097207840 2124431211 2140899670 2142085764 2147141360 2197011040 2214945824 2236243380 2254498428 2254827120 2305584260 2312306080 2366257530 2373156240 2422596995 2427921384 2446742480 2448098016 2524008032 2555706720 2569079604 2576569632 2608950610 2630248166 2634953440 2677607205 2704294320 2766701112 2768682280 2818123035 2832574948 2856114352 2907116394 2912316960 2936090976 2981657840 2997259538 3005997904 3034901730 3060122520 3130740732 3155010040 3211349505 3220712040 3237228512 3295516560 3322418736 3391635793 3425439472 3458376390 3468459120 3540718685 3570142940 3577989408 3670113720 3688934816 3757497380 3786012048 3876155192 3913425915 3945372249 3952430160 4046535640 4080163360 4153023420 4174320976 4248862422 4281799340 4284171528 4294282720 4472486760 4495889307 4508996856 4509654240 4611168520 4732515060 4746312480 4845193990 4855842768 4893484960 4957006159 5138159208 5217901220 5260496332 5355214410 5408588640 5533402224 5537364560 5636246070 5665149896 5712228704 5814232788 5963315680 5994519076 6011995808 6069803460 6120245040 6261481464 6310020080 6422699010 6441424080 6575620415 6591033120 6644837472 6783271586 6850878944 6916752780 6936918240 7081437370 7140285880 7267790985 7340227440 7493148845 7514994760 7572024096 7752310384 7826851830 7890744498 7904860320 8093071280 8306046840 8348641952 8497724844 8563598680 8568343056 8944973520 8991778614 9017993712 9205868581 9222337040 9465030120 9690387980 9711685536 9914012318 10174907379 10276318416 10435802440 10520992664 10622156055 10710428820 11066804448 11074729120 11272492140 11330299792 11628465576 11989038152 12139606920 12240490080 12522962928 12620040160 12845398020 12882848160 13151240830 13566543172 13833505560 14162874740 14280571760 14535581970 14680454880 14871018477 14986297690 15029989520 15504620768 15653703660 15781488996 16186142560 16612093680 16958178965 16995449688 17127197360 17136686112 17889947040 17983557228 18035987424 18411737162 18444674080 18930060240 19380775960 19726861245 19828024636 20349814758 20552636832 20871604880 21041985328 21244312110 21420857640 22479446535 22544984280 22660599584 23256931152 23978076304 24279213840 24785030795 25045925856 25690796040 26302481660 27133086344 27617605743 27667011120 28325749480 28561143520 29071163940 29742036954 29972595380 30059979040 31307407320 31562977992 33224187360 33916357930 33990899376 34254394720 35967114456 36823474324 37860120480 38761551920 39453722490 39656049272 40699629516 41743209760 42083970656 42488624220 42841715280 44958893070 45089968560 46029342905 46513862304 47956152608 48558427680 49570061590 50874536895 51381592080 52604963320 54266172688 55235211486 55334022240 56651498960 58142327880 59484073908 59945190760 62614814640 63125955984 64441080067 67832715860 67981798752 71934228912 73646948648 74355092385 77523103840 78907444980 79312098544 81399259032 84977248440 85683430560 89917786140 90179937120 92058685810 99140123180 101749073790 102763184160 105209926640 108532345376 110470422972 113302997920 116284655760 118968147816 119890381520 125229629280 126251911968 128882160134 135665431720 138088028715 143868457824 147293897296 148710184770 157814889960 158624197088 162798518064 169954496880 179835572280 184117371620 193323240201 198280246360 203498147580 210419853280 220940845944 232569311520 237936295632 239780763040 257764320268 271330863440 276176057430 294587794592 297420369540 315629779920 322205400335 325597036128 339908993760 359671144560 368234743240 386646480402 396560492720 406996295160 441881691888 475872591264 515528640536 542661726880 552352114860 594840739080 631259559840 644410800670 719342289120 736469486480 773292960804 793120985440 813992590320 883763383776 966616201005 1031057281072 1104704229720 1189681478160 1288821601340 1472938972960 1546585921608 1627985180640 1933232402010 2062114562144 2209408459440 2379362956320 2577643202680 3093171843216 3866464804020 4418816918880 5155286405360 6186343686432 7732929608040 10310572810720 15465859216080 30931718432160
- Sum of all divisors σ(n): 132222196592640
- Sum of proper divisors (its aliquot sum) s(n): 101290478160480
- 30931718432160 is an abundant number, because the sum of its proper divisors (101290478160480) is greater than itself. Its abundance is 70358759728320
Bases of 30931718432160
- Binary: 1110000100001110110100001011011100101101000002
- Hexadecimal: 0x1C21DA16E5A0
- Base-36: AYPU2IRHC
Squares and roots of 30931718432160
- 30931718432160 squared (309317184321602) is 956771205166426688522265600
- 30931718432160 cubed (309317184321603) is 29594577522206297421767513972083101696000
-
The
square root of 30931718432160 is 5561629.1167390873 -
The
cube root of 30931718432160 is 31390.7252254107
Scales and comparisons
How big is 30931718432160?- 30,931,718,432,160 seconds is equal to 983,532 years, 50 weeks, 2 days, 8 hours, 56 minutes.
-
To count from 1 to 30,931,718,432,160 would take you about two million, four hundred fifty-eight thousand, eight hundred thirty-two 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 30931718432160 cubic inches would be around 2615.9 feet tall.
Recreational maths with 30931718432160
- 30931718432160 backwards is 06123481713903
- 30931718432160 is a
Harshad number . - The number of decimal digits it has is: 14
- The sum of 30931718432160's digits is 48
- 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 30931718432160 - Facts about the integer". Numbermatics.com. 2024. Web. 25 June 2024.
APA style:
Numbermatics. (2024). Number 30931718432160 - Facts about the integer. Retrieved 25 June 2024, from https://numbermatics.com/n/30931718432160/
Chicago style:
Numbermatics. 2024. "Number 30931718432160 - Facts about the integer". https://numbermatics.com/n/30931718432160/
The information we have on file for 30931718432160 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 30931718432160, math, Factors of 30931718432160, curriculum, school, college, exams, university, Prime factorization of 30931718432160, STEM, science, technology, engineering, physics, economics, calculator, thirty trillion, nine hundred thirty-one billion, seven hundred eighteen million, four hundred thirty-two thousand, one hundred sixty.