189888742613313900
189,888,742,613,313,900 is an even composite number composed of seven prime numbers multiplied together.
What does the number 189888742613313900 look like?
This visualization shows the relationship between its 7 prime factors (large circles) and 1944 divisors.
189888742613313900 is an even composite number. It is composed of seven distinct prime numbers multiplied together. It has a total of one thousand, nine hundred forty-four divisors.
Prime factorization of 189888742613313900:
22 × 38 × 52 × 13 × 31 × 113 × 25212
(2 × 2 × 3 × 3 × 3 × 3 × 3 × 3 × 3 × 3 × 5 × 5 × 13 × 31 × 113 × 2521 × 2521)See below for interesting mathematical facts about the number 189888742613313900 from the Numbermatics database.
Names of 189888742613313900
- Cardinal: 189888742613313900 can be written as One hundred eighty-nine quadrillion, eight hundred eighty-eight trillion, seven hundred forty-two billion, six hundred thirteen million, three hundred thirteen thousand, nine hundred.
Scientific notation
- Scientific notation: 1.898887426133139 × 1017
Factors of 189888742613313900
Divisors of 189888742613313900
- Number of divisors d(n): 1944
-
Complete list of divisors:
1 2 3 4 5 6 9 10 12 13 15 18 20 25 26 27 30 31 36 39 45 50 52 54 60 62 65 75 78 81 90 93 100 108 113 117 124 130 135 150 155 156 162 180 186 195 225 226 234 243 260 270 279 300 310 324 325 339 351 372 390 403 405 450 452 465 468 486 540 558 565 585 620 650 675 678 702 729 775 780 806 810 837 900 930 972 975 1017 1053 1116 1130 1170 1209 1215 1300 1350 1356 1395 1404 1458 1469 1550 1612 1620 1674 1695 1755 1860 1950 2015 2025 2034 2106 2187 2260 2325 2340 2418 2430 2511 2521 2700 2790 2825 2916 2925 2938 3051 3100 3159 3348 3390 3503 3510 3627 3645 3900 4030 4050 4068 4185 4212 4374 4407 4650 4836 4860 5022 5042 5085 5265 5580 5650 5850 5876 6045 6075 6102 6318 6561 6780 6975 7006 7020 7254 7290 7345 7533 7563 8060 8100 8370 8475 8748 8775 8814 9153 9300 9477 10044 10075 10084 10170 10509 10530 10881 10935 11300 11700 12090 12150 12204 12555 12605 12636 13122 13221 13950 14012 14508 14580 14690 15066 15126 15255 15795 16740 16950 17515 17550 17628 18135 18225 18306 18954 20150 20340 20925 21018 21060 21762 21870 22035 22599 22689 24180 24300 25110 25210 25425 26244 26325 26442 27459 27900 28431 29380 30132 30225 30252 30510 31527 31590 32643 32773 32805 33900 35030 35100 36270 36450 36612 36725 37665 37815 37908 39663 40300 41850 42036 43524 43740 44070 45198 45378 45539 45765 47385 50220 50420 50850 52545 52650 52884 54405 54675 54918 56862 60450 61020 62775 63025 63054 63180 65286 65546 65610 66105 67797 68067 70060 72540 72900 73450 75330 75630 76275 78151 78975 79326 82377 83700 85293 87575 88140 90396 90675 90756 91078 91530 94581 94770 97929 98319 101700 105090 105300 108810 109350 109836 110175 112995 113445 113724 118989 120900 125550 126050 126108 130572 131092 131220 132210 135594 136134 136617 137295 142155 146900 150660 151260 152550 156302 157635 157950 158652 163215 163865 164025 164754 170586 175150 181350 182156 183060 188325 189075 189162 189540 195858 196638 198315 203391 204201 210180 217620 218700 220350 225990 226890 227695 228825 234453 236925 237978 247131 251100 252100 262725 264420 271188 272025 272268 273234 274590 283743 284310 284873 293787 294957 305100 312604 315270 315900 326430 327730 328050 329508 330525 338985 340335 341172 350300 356967 362700 376650 378150 378324 390755 391716 393276 396630 406782 408402 409851 411885 426465 440700 451980 453780 455390 457650 468906 472905 473850 475956 489645 491595 494262 525450 544050 546468 549180 564975 567225 567486 568620 569746 587574 589914 594945 612603 630540 652860 655460 656100 661050 677970 680670 683085 686475 703359 710775 713934 741393 753300 756300 781510 788175 793260 813564 816075 816804 819325 819702 823770 851229 852930 854619 881361 884871 910780 915300 937812 945810 947700 979290 983190 988524 991575 1015963 1016955 1021005 1050900 1070901 1088100 1129950 1134450 1134972 1138475 1139492 1172265 1175148 1179828 1189890 1225206 1229553 1235655 1322100 1355940 1361340 1366170 1372950 1406718 1418715 1421550 1424365 1427868 1468935 1474785 1482786 1563020 1576350 1632150 1638650 1639404 1647540 1694925 1701675 1702458 1705860 1709238 1762722 1769742 1784835 1837809 1891620 1953775 1958580 1966380 1983150 2031926 2033910 2042010 2049255 2059425 2110077 2132325 2141802 2259900 2268900 2276950 2344530 2364525 2379780 2448225 2450412 2457975 2459106 2471310 2553687 2563857 2644083 2654613 2732340 2745900 2813436 2837430 2843100 2848730 2937870 2949570 2965572 2974725 3047889 3063015 3152700 3212703 3264300 3277300 3389850 3403350 3404916 3415425 3418476 3516795 3525444 3539484 3569670 3675618 3688659 3703349 3706965 3907550 3966300 4063852 4067820 4084020 4098510 4118850 4220154 4256145 4264650 4273095 4283604 4406805 4424355 4553900 4689060 4729050 4896450 4915950 4918212 4942620 5079815 5084775 5105025 5107374 5127714 5288166 5309226 5354505 5513427 5674860 5697460 5861325 5875740 5899140 5949450 6095778 6126030 6147765 6178275 6330231 6355441 6425406 6779700 6806700 6830850 7033590 7093575 7121825 7139340 7344675 7351236 7373925 7377318 7406698 7413930 7661061 7691571 7815100 7963839 8197020 8237700 8440308 8512290 8529300 8546190 8813610 8831063 8848710 8924175 9143667 9189045 9458100 9638109 9792900 9831900 10159630 10169550 10210050 10214748 10246275 10255428 10550385 10576332 10618452 10709010 11026854 11065977 11110047 11722650 11898900 12191556 12252060 12295530 12356550 12660462 12710882 12768435 12819285 12850812 13220415 13273065 13661700 14067180 14187150 14243650 14689350 14747850 14754636 14813396 14827860 15239445 15315075 15322122 15383142 15927678 16063515 16540281 17024580 17092380 17583975 17627220 17662126 17697420 17848350 18287334 18378090 18443295 18516745 18534825 18990693 19066323 19276218 20319260 20339100 20420100 20492550 21100770 21280725 21365475 21418020 22034025 22053708 22121775 22131954 22220094 22983183 23074713 23445300 23891517 24591060 24713100 25320924 25399075 25421764 25536870 25638570 26440830 26493189 26546130 26772525 27431001 27567135 28374300 28487300 29378700 29495700 30478890 30630150 30644244 30738825 30766284 31651155 31777205 31855356 32127030 33080562 33197931 33330141 35167950 35324252 35696700 36574668 36756180 36886590 37033490 37069650 37981386 38132646 38305305 38457855 38552436 39819195 40985100 42201540 42561450 42730950 44068050 44155315 44243550 44263908 44440188 45718335 45945225 45966366 46149426 47783034 48190545 50798150 51073740 51277140 52751925 52881660 52986378 53092260 53545050 54862002 55134270 55329885 55550235 56972079 57198969 60957780 61260300 61477650 63302310 63554410 63842175 64096425 64254060 66102075 66161124 66365325 66395862 66660282 69224139 70335900 71674551 73773180 74066980 74139300 75962772 76197225 76265292 76610610 76915710 79479567 79638390 80317575 82293003 82620733 82701405 85122900 85461900 88136100 88310630 88487100 91436670 91890450 91932732 92216475 92298852 92583725 94953465 95331615 95566068 96381090 99593793 99990423 101596300 105503850 105972756 107090100 109724004 110268540 110659770 111100470 113944158 114397938 114803819 114915915 115373565 119457585 122955300 126604620 127108820 127684350 128192850 132204150 132465945 132730650 132791724 133320564 137155005 137835675 138448278 143349102 152394450 153221220 153831420 158255775 158886025 158959134 159276780 160635150 164586006 165241466 165402810 165989655 166650705 170916237 171596907 176621260 182873340 183780900 184432950 185167450 189906930 190663230 191526525 192289275 192762180 197018671 199095975 199187586 199980846 207672417 211007700 215023653 220776575 221319540 222200940 227888316 228591675 228795876 229607638 229831830 230747130 238438701 238915170 240952725 246879009 247862199 255368700 256385700 264408300 264931890 265461300 274310010 275671350 276649425 276896556 277751175 284860395 285994845 286698204 298781379 299971269 304788900 316511550 317772050 317918268 321270300 329172012 330482932 330805620 331979310 333301410 341832474 343193814 344411457 346120695 358372755 368865900 370334900 379813860 381326460 383053050 384578550 394037342 397397835 398191950 398375172 399961692 411465015 413103665 413507025 415344834 430047306 441553150 457183350 459215276 459663660 461494260 474767325 476658075 476877402 477830340 481905450 493758018 495724398 497968965 499952115 512748711 514790721 529863780 548620020 551342700 553298850 555502350 569720790 571989690 574019095 574579575 576867825 591056013 597287925 597562758 599942538 623017251 633023100 635544100 662329725 663958620 666602820 683664948 685775025 686387628 688822914 692241390 715316103 716745510 718164833 740637027 743586597 766106100 769157100 788074684 794795670 796383900 822930030 826207330 827014050 829948275 830689668 833253525 854581185 857984535 860094612 883106300 899913807 914366700 949534650 953316150 953754804 963810900 985093355 987516036 991448796 995937930 999904230 1025497422 1029581442 1033234371 1038362085 1075118265 1106597700 1111004700 1139441580 1143979380 1148038190 1149159150 1153735650 1182112026 1192193505 1194575850 1195125516 1199885076 1234395045 1239310995 1246034502 1324659450 1371550050 1377645828 1384482780 1424301975 1429974225 1430632206 1433491020 1436329666 1481274054 1487173194 1493906895 1499856345 1544372163 1589591340 1645860060 1652414660 1654028100 1659896550 1666507050 1709162370 1715969070 1722057285 1730603475 1773168039 1791863775 1799827614 1869051753 1899069300 1906632300 1970186710 1986989175 1991875860 1999808460 2050994844 2057325075 2059162884 2065518325 2066468742 2076724170 2145948309 2150236530 2154494499 2221911081 2230759791 2296076380 2298318300 2307471300 2364224052 2384387010 2389151700 2468790090 2478621990 2489844825 2492069004 2499760575 2561242723 2563743555 2573953605 2649318900 2699741421 2743100100 2848603950 2859948450 2861264412 2870095475 2872659332 2955280065 2962548108 2974346388 2987813790 2999712690 3088744326 3099703113 3115086255 3319793100 3333014100 3418324740 3431938140 3444114570 3461206950 3546336078 3576580515 3583727550 3590824165 3599655228 3703185135 3717932985 3738103506 3940373420 3973978350 4114650150 4131036650 4132937484 4153448340 4272905925 4289922675 4291896618 4300473060 4308988998 4443822162 4461519582 4499569035 4633116489 4768774020 4925466775 4937580180 4957243980 4979689650 4999521150 5122485446 5127487110 5147907210 5166171855 5191810425 5319504117 5375591325 5399482842 5697207900 5719896900 5740190950 5910560130 5960967525 5975627580 5999425380 6171975225 6177488652 6196554975 6199406226 6230172510 6437844927 6463483497 6665733243 6692279373 6888229140 6922413900 7092672156 7153161030 7167455100 7181648330 7406370270 7435865970 7469534475 7476207012 7499281725 7683728169 7721860815 7947956700 8099224263 8229300300 8262073300 8545811850 8579845350 8583793236 8610286425 8617977996 8865840195 8887644324 8923039164 8999138070 9266232978 9299109339 9336142829 9345258765 9850933550 9959379300 9999042300 10244970892 10254974220 10295814420 10332343710 10383620850 10639008234 10729741545 10751182650 10772472495 10798965684 11109555405 11153798955 11480381900 11821120260 11921935050 12343950450 12393109950 12398812452 12460345020 12806213615 12818717775 12869768025 12875689854 12926966994 13331466486 13384558746 13498707105 13899349467 14306322060 14363296660 14776400325 14812740540 14871731940 14939068950 14998563450 15367456338 15443721630 15498515565 15575431275 15958512351 16198448526 17091623700 17159690700 17220572850 17731680390 17882902575 17954120825 17998276140 18515925675 18532465956 18589664925 18598218678 18672285658 18690517530 19313534781 19390450491 19701867100 20076838119 20664687420 20767241700 21278016468 21459483090 21502365300 21544944990 22219110810 22263109823 22307597910 22497845175 23051184507 23165582445 23843870100 24297672789 24687900900 24786219900 25612427230 25637435550 25739536050 25751379708 25830859275 25853933988 26597520585 26662932972 26769117492 26997414210 27798698934 27897328017 28008428487 29552800650 29878137900 29997126900 30734912676 30887443260 30997031130 31150862550 31917024702 32189224635 32317417485 32396897052 33328666215 33461396865 34441145700 35463360780 35765805150 35908241650 37031851350 37179329850 37196437356 37344571316 37381035060 38418640845 38609304075 38627069562 38780900982 40153676238 40496121315 41698048401 42918966180 43089889980 44329200975 44438221620 44526219646 44615195820 44995690350 46102369014 46331164890 46495546695 46680714145 46726293825 47875537053 48595345578 51224854460 51274871100 51479072100 51661718550 53195041170 53648707725 53862362475 53994828420 55547777025 55597397868 55768994775 55794656034 56016856974 57940604343 58171351473 59105601300 60230514357 61994062260 62301725100 63834049404 64031068075 64378449270 64634834970 66657332430 66789329469 66922793730 67493535525 69153553521 69496747335 71531610300 71816483300 74063702700 74358659700 76837281690 77218608150 77254139124 77492577825 77561801964 79792561755 80307352476 80992242630 83396096802 83691984051 84025285461 88658401950 89052439292 89991380700 92204738028 92662329780 92991093390 93361428290 93452587650 95751074106 96567673905 96952252455 97190691156 100384190595 103323437100 106390082340 107297415450 107724724950 111095554050 111315549115 111537989550 111589312068 112033713948 115255922535 115827912225 115881208686 116342702946 120461028714 121488363945 128062136150 128756898540 129269669940 132987602925 133314664860 133578658938 133845587460 134987071050 138307107042 138993494670 139486640085 140042142435 143626611159 153674563380 154437216300 154985155650 159585123510 160946123175 161587087425 161984485260 166643331075 166792193604 167306984325 167383968102 168050570922 174514054419 177316803900 180691543071 185982186780 186722856580 186905175300 191502148212 192093204225 193135347810 193904504910 200367988407 200768381190 202480606575 207460660563 208490242005 214594830900 215449449900 222191108100 222631098230 223075979100 230511845070 231655824450 231762417372 232477733475 232685405892 233403570725 239377685265 240922057428 242976727890 251075952153 252075856383 256124272300 265975205850 267157317876 269974142100 276614214084 277986989340 278973280170 280084284870 287253222318 289420427699 289703021715 290856757365 301152571785 309970311300 319170247020 321892246350 323174174850 333286662150 333946647345 334613968650 334767936204 336101141844 345767767605 347483736675 349028108838 361383086142 384186408450 386270695620 387809009820 398962808775 400735976814 401536762380 404961213150 414921321126 416980484010 418459920255 420126427305 430879833477 445262196460 461023690140 463311648900 464955466950 466807141450 478755370530 482838369525 484761262275 485953455780 501920952975 502151904306 504151712766 523542163257 531950411700 542074629213 556577745575 557946560340 560168569740 574506444636 576279612675 578840855398 579406043430 581713514730 601103965221 602305143570 607441819725 622381981689 643784492700 646348349700 666573324300 667893294690 669227937300 691535535210 694967473350 697433200425 698056217676 700210712175 718133055795 722766172284 753227856459 756227569149 768372816900 797925617550 801471953628 809922426300 829842642252 833960968020 836919840510 840252854610 861759666954 868261283097 872570272095 903457715355 929910933900 933614282900 957510741060 965676739050 969522524550 1001839942035 1003841905950 1004303808612 1008303425532 1037303302815 1042451210025 1047084326514 1084149258426 1113155491150 1152559225350 1157681710796 1158812086860 1163427029460 1196888426325 1202207930442 1204610287140 1214883639450 1244763963378 1255379760765 1260379281915 1292639500431 1335786589380 1383071070420 1389934946700 1394866400850 1400421424350 1436266111590 1447102138495 1448515108575 1454283786825 1505762858925 1506455712918 1512455138298 1570626489771 1595851235100 1669733236725 1673839681020 1680505709220 1723519333908 1728838838025 1736522566194 1745140544190 1803311895663 1806915430710 1867145945067 1931353478100 1939045049100 2003679884070 2007683811900 2074606605630 2084902420050 2092299601275 2094168653028 2100632136525 2154399167385 2168298516852 2226310982300 2268682707447 2305118450700 2393776852650 2404415860884 2429767278900 2489527926756 2510759521530 2520758563830 2585279000862 2604783849291 2617710816285 2710373146065 2789732801700 2800842848700 2872532223180 2894204276990 2897030217150 2908567573650 3005519826105 3011525717850 3012911425836 3024910276596 3111909908445 3141252979542 3339466473450 3457677676050 3473045132388 3490281088380 3590665278975 3606623791326 3613830861420 3734291890134 3766139282295 3781137845745 4007359768140 4149213211260 4169804840100 4184599202550 4201264273050 4308798334770 4341306415485 4362851360475 4517288576775 4537365414894 4711879469313 4787553705300 5009199710175 5021519043060 5041517127660 5170558001724 5186516514075 5209567698582 5235421632570 5409935686989 5420746292130 5601437835201 5788408553980 5794060434300 5817135147300 6011039652210 6023051435700 6223819816890 6276898803825 6282505959084 6301896409575 6463197502155 6678932946900 6806048122341 6915355352100 7181330557950 7213247582652 7235510692475 7468583780268 7532278564590 7562275691490 7814351547873 7853132448855 8369198405100 8402528546100 8617596669540 8682612830970 8725702720950 9016559478315 9034577153550 9074730829788 9335729725335 9423758938626 10018399420350 10373033028150 10419135397164 10470843265140 10771995836925 10819871373978 10841492584260 11202875670402 11343413537235 12022079304420 12447639633780 12553797607650 12603792819150 12926395004310 13023919246455 13088554081425 13551865730325 13612096244682 14362661115900 14471021384950 15027599130525 15064557129180 15124551382980 15559549542225 15628703095746 15706264897710 16229807060967 16804313505603 17365225661940 17451405441900 18033118956630 18069154307100 18671459450670 18830696411475 18847517877252 18905689228725 20036798840700 20418144367023 20746066056300 21543991673850 21639742747956 21706532077425 22405751340804 22686827074470 23443054643619 23559397346565 25107595215300 25207585638300 25852790008620 26047838492910 26177108162850 27049678434945 27103731460650 27224192489364 28007189176005 28942042769900 30055198261050 31119099084450 31257406191492 31412529795420 32315987510775 32459614121934 33608627011206 34030240611705 36066237913260 37342918901340 37661392822950 37811378457450 39071757739365 39265662244275 40836288734046 43087983347700 43413064154850 45082797391575 45373654148940 46678648626675 46886109287238 47118794693130 48689421182901 52095676985820 52354216325700 54099356869890 54207462921300 56014378352010 56717067686175 60110396522100 61254433101069 62238198168900 64631975021550 64919228243868 65119596232275 67217254022412 68060481223410 70329163930857 75322785645900 75622756914900 78143515478730 78531324488550 81149035304835 81672577468092 84021567528015 86826128309700 90165594783150 93357297253350 93772218574476 94237589386260 97378842365802 102090721835115 108198713739780 112028756704020 113434135372350 117215273218095 117796986732825 122508866202138 129263950043100 130239192464550 135248392174725 136120962446820 140035945880025 140658327861714 146068263548703 156287030957460 157062648977100 162298070609670 168043135056030 170151203058525 180331189566300 186714594506700 194757684731604 195358788696825 204181443670230 210987491792571 226868270744700 234430546436190 235593973465650 243447105914505 245017732404276 260478384929100 270496784349450 280071891760050 281316655723428 292136527097406 306272165505345 324596141219340 336086270112060 340302406117050 351645819654285 390717577393650 405745176524175 408362887340460 420107837640075 421974983585142 468861092872380 471187946931300 486894211829010 510453609175575 540993568698900 560143783520100 584273054194812 586076366090475 612544331010690 632962475377713 680604812234100 703291639308570 730341317743515 781435154787300 811490353048350 840215675280150 843949967170284 973788423658020 1020907218351150 1054937458962855 1172152732180950 1217235529572525 1225088662021380 1265924950755426 1406583278617140 1460682635487030 1531360827526725 1622980706096700 1680431350560300 1758229098271425 1898887426133139 2041814436702300 2109874917925710 2344305464361900 2434471059145050 2531849901510852 2921365270974060 3062721655053450 3164812376888565 3516458196542850 3651706588717575 3797774852266278 4219749835851420 4868942118290100 5274687294814275 6125443310106900 6329624753777130 7032916393085700 7303413177435150 7595549704532556 9494437130665695 10549374589628550 12659249507554260 14606826354870300 15824061884442825 18988874261331390 21098749179257100 31648123768885650 37977748522662780 47472185653328475 63296247537771300 94944371306656950 189888742613313900
- Sum of all divisors σ(n): 693425530128868992
- Sum of proper divisors (its aliquot sum) s(n): 503536787515555092
- 189888742613313900 is an abundant number, because the sum of its proper divisors (503536787515555092) is greater than itself. Its abundance is 313648044902241192
Bases of 189888742613313900
- Binary: 10101000101001111011001110001010100100111111101001011011002
- Hexadecimal: 0x2A29ECE2A4FE96C
- Base-36: 1FXPXW2XX6R0
Squares and roots of 189888742613313900
- 189888742613313900 squared (1898887426133139002) is 36057734571265374220381539933210000
- 189888742613313900 cubed (1898887426133139003) is 6846957879222201073935075976001672666262764619000000
-
The
square root of 189888742613313900 is 435762254.6909196219 -
The
cube root of 189888742613313900 is 574777.4741839783
Scales and comparisons
How big is 189888742613313900?- 189,888,742,613,313,900 seconds is equal to 6,037,874,650 years, 34 weeks, 1 day, 6 hours, 45 minutes.
-
To count from 1 to 189,888,742,613,313,900 would take you about eighteen billion, one hundred thirteen million, six hundred twenty-three thousand, nine hundred fifty-one 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 189888742613313900 cubic inches would be around 47898.1 feet tall.
Recreational maths with 189888742613313900
- 189888742613313900 backwards is 009313316247888981
- 189888742613313900 is a
Harshad number . - The number of decimal digits it has is: 18
- The sum of 189888742613313900's digits is 81
- 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 189888742613313900 - Facts about the integer". Numbermatics.com. 2024. Web. 1 June 2024.
APA style:
Numbermatics. (2024). Number 189888742613313900 - Facts about the integer. Retrieved 1 June 2024, from https://numbermatics.com/n/189888742613313900/
Chicago style:
Numbermatics. 2024. "Number 189888742613313900 - Facts about the integer". https://numbermatics.com/n/189888742613313900/
The information we have on file for 189888742613313900 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 189888742613313900, math, Factors of 189888742613313900, curriculum, school, college, exams, university, Prime factorization of 189888742613313900, STEM, science, technology, engineering, physics, economics, calculator, one hundred eighty-nine quadrillion, eight hundred eighty-eight trillion, seven hundred forty-two billion, six hundred thirteen million, three hundred thirteen thousand, nine hundred.