38408895446425600
38,408,895,446,425,600 is an even composite number composed of six prime numbers multiplied together.
38408895446425600 is an even composite number. It is composed of six distinct prime numbers multiplied together. It has a total of two thousand and sixteen divisors.
Prime factorization of 38408895446425600:
213 × 52 × 293 × 372 × 41 × 137
(2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 2 × 5 × 5 × 29 × 29 × 29 × 37 × 37 × 41 × 137)See below for interesting mathematical facts about the number 38408895446425600 from the Numbermatics database.
Names of 38408895446425600
- Cardinal: 38408895446425600 can be written as Thirty-eight quadrillion, four hundred eight trillion, eight hundred ninety-five billion, four hundred forty-six million, four hundred twenty-five thousand, six hundred.
Scientific notation
- Scientific notation: 3.84088954464256 × 1016
Factors of 38408895446425600
Divisors of 38408895446425600
- Number of divisors d(n): 2016
-
Complete list of divisors:
1 2 4 5 8 10 16 20 25 29 32 37 40 41 50 58 64 74 80 82 100 116 128 137 145 148 160 164 185 200 205 232 256 274 290 296 320 328 370 400 410 464 512 548 580 592 640 656 685 725 740 800 820 841 925 928 1024 1025 1073 1096 1160 1184 1189 1280 1312 1369 1370 1450 1480 1517 1600 1640 1682 1850 1856 2048 2050 2146 2192 2320 2368 2378 2560 2624 2738 2740 2900 2960 3034 3200 3280 3364 3425 3700 3712 3973 4096 4100 4205 4292 4384 4640 4736 4756 5069 5120 5248 5365 5476 5480 5617 5800 5920 5945 6068 6400 6560 6728 6845 6850 7400 7424 7585 7946 8192 8200 8410 8584 8768 9280 9472 9512 10138 10240 10496 10730 10952 10960 11234 11600 11840 11890 12136 12800 13120 13456 13690 13700 14800 14848 15170 15892 16400 16820 17168 17536 18560 18944 19024 19865 20276 20480 20992 21025 21460 21904 21920 22468 23200 23680 23780 24272 24389 25345 25600 26240 26825 26912 27380 27400 28085 29600 29696 29725 30340 31117 31784 32800 33640 34225 34336 34481 35072 37120 37888 37925 38048 39701 39730 40552 40960 41984 42050 42920 43808 43840 43993 44936 46400 47360 47560 48544 48778 50690 51200 52480 53650 53824 54760 54800 56129 56170 59200 59392 59450 60680 62234 63568 65600 67280 68450 68672 68962 70144 74240 75776 75850 76096 79402 79460 81104 83968 84100 85840 87616 87680 87986 89872 92800 94720 95120 97088 97556 99325 101380 102400 104960 107300 107648 109520 109600 112258 112340 115217 118400 118784 118900 121360 121945 124468 126725 127136 131200 134560 136900 137344 137924 140288 140425 147001 148480 151552 151700 152192 155585 158804 158920 162208 162893 167936 168200 171680 172405 175232 175360 175972 179744 185600 187553 189440 190240 194176 195112 198505 198650 202760 204800 207829 209920 214600 215296 219040 219200 219965 224516 224680 230434 236800 237568 237800 242720 243890 248936 253450 254272 262400 269120 273800 274688 275848 280576 280645 280850 294002 296960 303104 303400 304384 311170 317608 317840 324416 325786 335872 336400 343360 344810 350464 350720 351944 359488 371200 375106 378880 380480 388352 390224 397010 397300 405520 415658 419840 429200 430592 438080 438400 439930 449032 449360 460868 473600 475600 485440 487780 497872 506900 508544 524800 538240 547600 549376 551696 561152 561290 561700 576085 588004 593920 606800 608768 609725 622340 635216 635680 648832 651572 672800 686720 689620 700928 701440 703888 718976 735005 742400 750212 757760 760960 776704 777925 780448 794020 794600 811040 814465 831316 839680 858400 861184 862025 876160 876800 879860 898064 898720 902393 921736 937765 947200 951200 970880 975560 992525 995744 999949 1013800 1017088 1039145 1049600 1076480 1095200 1098752 1099825 1103392 1122304 1122580 1123400 1151329 1152170 1176008 1187840 1213600 1217536 1219450 1244680 1270432 1271360 1275797 1297664 1303144 1345600 1373440 1379240 1401856 1402880 1403225 1407776 1437952 1470010 1484800 1500424 1515520 1521920 1553408 1555850 1560896 1588040 1589200 1622080 1627741 1628930 1662632 1679360 1716800 1722368 1724050 1752320 1753600 1759720 1796128 1797440 1804786 1843472 1875530 1894400 1902400 1941760 1951120 1985050 1991488 1999898 2027600 2034176 2078290 2099200 2152960 2190400 2197504 2199650 2206784 2245160 2246800 2302658 2304340 2352016 2427200 2435072 2438900 2489360 2540864 2542720 2551594 2595328 2606288 2691200 2746880 2758480 2803712 2805760 2806450 2815552 2875904 2880425 2940020 2969600 3000848 3043840 3106816 3111700 3121792 3176080 3178400 3244160 3255482 3257860 3325264 3341293 3433600 3444736 3448100 3504640 3507200 3519440 3592256 3594880 3609572 3675025 3686944 3751060 3788800 3804800 3883520 3902240 3970100 3982976 3999796 4055200 4068352 4072325 4156580 4198400 4263029 4305920 4380800 4395008 4399300 4413568 4490320 4493600 4511965 4605316 4608680 4688825 4704032 4723897 4854400 4870144 4877800 4978720 4999745 5081728 5085440 5103188 5190656 5195725 5212576 5382400 5439037 5493760 5516960 5607424 5611520 5612900 5631104 5751808 5756645 5760850 5880040 5939200 6001696 6027041 6087680 6213632 6223400 6243584 6352160 6356800 6378985 6488320 6510964 6515720 6650528 6682586 6867200 6889472 6896200 7009280 7014400 7038880 7184512 7189760 7219144 7350050 7373888 7502120 7577600 7609600 7689673 7767040 7804480 7940200 7965952 7999592 8110400 8136704 8138705 8144650 8313160 8396800 8526058 8611840 8761600 8790016 8798600 8827136 8980640 8987200 9023930 9210632 9217360 9377650 9408064 9447794 9708800 9740288 9755600 9957440 9999490 10163456 10170880 10206376 10381312 10391450 10425152 10764800 10878074 10987520 11033920 11214848 11225800 11262208 11503616 11513290 11521700 11760080 12003392 12054082 12175360 12427264 12446800 12487168 12704320 12713600 12757970 12976640 13021928 13031440 13301056 13365172 13734400 13792400 14018560 14028800 14077760 14369024 14379520 14438288 14700100 14747776 15004240 15219200 15379346 15534080 15608960 15880400 15931904 15999184 16220800 16273408 16277410 16289300 16626320 16706465 17052116 17223680 17523200 17597200 17654272 17961280 17974400 18047860 18421264 18434720 18755300 18816128 18895588 19417600 19511200 19914880 19998980 20326912 20341760 20412752 20762624 20782900 20850304 21315145 21529600 21756148 21975040 22067840 22451600 22524416 22559825 23007232 23026580 23043400 23520160 23619485 24006784 24108164 24350720 24893600 24974336 24998725 25408640 25427200 25515940 25953280 26043856 26062880 26602112 26730344 27195185 27468800 27584800 28037120 28057600 28155520 28738048 28759040 28783225 28876576 29400200 29495552 30008480 30135205 30438400 30758692 31068160 31217920 31760800 31863808 31894925 31998368 32441600 32546816 32554820 32578600 33252640 33388541 33412930 34104232 34447360 35046400 35194400 35308544 35922560 35948800 36095720 36842528 36869440 36998113 37510600 37632256 37791176 38448365 38835200 39022400 39829760 39997960 40653824 40683520 40693525 40825504 41525248 41565800 41700608 42630290 43059200 43512296 43950080 44135680 44903200 45048832 45119650 46014464 46053160 46086800 47040320 47204489 47238970 48013568 48216328 48701440 49787200 49948672 49997450 50817280 50854400 51031880 51906560 52087712 52125760 53204224 53460688 54390370 54937600 55169600 56074240 56311040 57476096 57518080 57566450 57753152 58800400 58991104 60016960 60270410 60876800 61517384 62136320 62435840 63521600 63727616 63789850 63996736 64883200 65109640 65157200 66505280 66777082 66825860 68208464 70092800 70388800 70617088 71845120 71897600 72191440 73685056 73738880 73996226 75021200 75264512 75582352 76896730 77670400 78044800 79659520 79995920 81307648 81367040 81387050 81651008 83131600 83401216 83532325 85260580 86118400 87024592 88271360 89806400 90097664 90239300 92106320 92173600 94080640 94408978 94477940 96027136 96432656 99574400 99897344 99994900 101634560 101708800 102063760 103813120 104175424 104251520 106408448 106575725 106921376 108780740 109875200 110339200 112622080 114952192 115036160 115132900 115506304 117600800 117982208 118097425 120033920 120540820 121753600 123034768 123627841 124871680 127043200 127455232 127579700 127993472 129766400 130219280 130314400 133010560 133554164 133651720 135975925 136416928 136993013 140185600 140777600 141234176 143690240 143795200 144382880 147370112 147477760 147992452 150042400 150529024 150676025 151164704 153793460 155340800 156089600 157732073 159319040 159991840 162615296 162734080 162774100 163302016 166263200 166802432 166942705 167064650 170521160 172236800 174049184 174784189 176542720 179612800 180195328 180478600 184212640 184347200 184990565 188161280 188817956 188955880 192054272 192241825 192865312 199148800 199794688 199989800 203269120 203417600 204127520 207626240 208350848 208503040 212816896 213151450 213842752 217561480 219750400 220678400 223000517 225244160 229904384 230072320 230265800 231012608 235201600 235964416 236022445 236194850 240067840 241081640 243507200 246069536 247255682 249743360 254086400 254910464 255159400 255986944 259532800 260438560 260628800 266021120 267108328 267303440 271951850 272833856 273986026 280371200 281555200 282468352 287380480 287590400 288765760 294740224 294955520 295984904 300084800 301058048 301352050 302329408 307586920 310681600 312179200 315464146 318638080 319983680 325230592 325548200 326604032 332526400 333604864 333885410 334129300 341042320 348098368 349568378 353085440 359225600 360390656 360957200 368425280 368694400 369981130 376322560 377635912 377911760 384108544 384483650 385730624 398297600 399979600 406538240 406835200 408255040 416701696 417006080 425633792 426302900 427685504 435122960 441356800 446001034 450488320 459808768 460531600 462025216 470403200 471928832 472044890 472389700 480135680 482163280 492139072 494511364 499486720 508172800 510318800 511973888 519065600 520877120 521257600 532042240 534216656 534606880 543903700 545667712 547972052 563110400 574760960 575180800 577531520 589480448 589911040 591969808 600169600 602116096 602704100 604658816 615173840 618139205 624358400 630928292 637276160 639967360 651096400 653208064 665052800 667209728 667770820 668258600 682084640 684965065 696196736 699136756 706170880 718451200 721914400 736850560 737388800 739962260 752645120 755271824 755823520 768217088 768967300 771461248 788660365 796595200 799959200 813076480 813670400 816510080 833403392 834012160 834713525 851267584 852605800 855371008 870245920 873920945 882713600 892002068 900976640 921063200 924050432 924952825 940806400 943857664 944089780 944779400 960271360 964326560 984278144 989022728 998973440 1016345600 1020637600 1023947776 1038131200 1041754240 1042515200 1064084480 1068433312 1069213760 1087807400 1091335424 1095944104 1115002585 1126220800 1149521920 1150361600 1155063040 1178960896 1179822080 1180112225 1183939616 1200339200 1204232192 1205408200 1209317632 1230347680 1236278410 1248716800 1261856584 1274552320 1279934720 1302192800 1306416128 1330105600 1334419456 1335541640 1336517200 1364169280 1368930181 1369930130 1392393472 1398273512 1412341760 1436902400 1443828800 1473701120 1474777600 1479924520 1505290240 1510543648 1511647040 1536434176 1537934600 1542922496 1577320730 1593190400 1599918400 1626152960 1633020160 1666806784 1668024320 1669427050 1702535168 1705211600 1710742016 1740491840 1747841890 1765427200 1784004136 1801953280 1842126400 1848100864 1849905650 1881612800 1888179560 1889558800 1920542720 1928653120 1968556288 1978045456 2032691200 2041275200 2047895552 2083508480 2085030400 2128168960 2136866624 2138427520 2175614800 2182670848 2191888208 2230005170 2252441600 2299043840 2310126080 2357921792 2359644160 2360224450 2367879232 2400678400 2410816400 2418635264 2460695360 2472556820 2497433600 2523713168 2559869440 2604385600 2612832256 2660211200 2671083280 2673034400 2728338560 2737860362 2739860260 2784786944 2796547024 2873804800 2887657600 2947402240 2949555200 2959849040 3010580480 3021087296 3023294080 3075869200 3085844992 3090696025 3154641460 3186380800 3199836800 3266040320 3333613568 3336048640 3338854100 3410423200 3421484032 3424825325 3480983680 3495683780 3530854400 3568008272 3684252800 3696201728 3699811300 3763225600 3776359120 3779117600 3841085440 3857306240 3937112576 3943301825 3956090912 4065382400 4082550400 4095791104 4167016960 4170060800 4256337920 4273733248 4276855040 4351229600 4365341696 4369604725 4383776416 4460010340 4504883200 4574230117 4620252160 4715843584 4719288320 4720448900 4735758464 4801356800 4821632800 4837270528 4921390720 4945113640 4994867200 5047426336 5068741481 5119738880 5208771200 5225664512 5320422400 5342166560 5346068800 5456677120 5475720724 5479720520 5569573888 5575012925 5593094048 5747609600 5775315200 5894804480 5899110400 5919698080 6021160960 6042174592 6046588160 6151738400 6171689984 6181392050 6309282920 6372761600 6399673600 6467014993 6532080640 6667227136 6672097280 6677708200 6820846400 6842968064 6844650905 6849650650 6961967360 6991367560 7061708800 7136016544 7368505600 7392403456 7399622600 7526451200 7552718240 7558235200 7682170880 7714612480 7874225152 7886603650 7912181824 8130764800 8165100800 8191582208 8334033920 8340121600 8512675840 8547466496 8553710080 8702459200 8730683392 8739209450 8767552832 8920020680 9009766400 9148460234 9240504320 9431687168 9440897800 9471516928 9602713600 9643265600 9674541056 9842781440 9890227280 10094852672 10137482962 10239477760 10417542400 10451329024 10640844800 10684333120 10692137600 10913354240 10951441448 10959441040 11139147776 11150025850 11186188096 11495219200 11550630400 11789608960 11798220800 11839396160 12084349184 12093176320 12303476800 12343379968 12362784100 12618565840 12799347200 12934029986 13064161280 13334454272 13355416400 13641692800 13685936128 13689301810 13699301300 13923934720 13982735120 14272033088 14737011200 14799245200 15052902400 15105436480 15116470400 15429224960 15748450304 15773207300 15824363648 16330201600 16668067840 16680243200 17094932992 17107420160 17404918400 17461366784 17478418900 17535105664 17840041360 18296920468 18481008640 18881795600 18943033856 19205427200 19286531200 19349082112 19685562880 19780454560 20189705344 20274965924 20478955520 20835084800 21281689600 21368666240 21384275200 21826708480 21902882896 21918882080 22278295552 22300051700 22372376192 22871150585 23101260800 23579217920 23596441600 23678792320 24168698368 24186352640 24606953600 24686759936 24725568200 25237131680 25343707405 25598694400 25868059972 26128322560 26710832800 27283385600 27371872256 27378603620 27398602600 27847869440 27965470240 28544066176 29474022400 29598490400 30105804800 30210872960 30232940800 30858449920 31496900608 31546414600 31648727296 32335074965 32660403200 33336135680 33360486400 34189865984 34214840320 34223254525 34809836800 34922733568 34956837800 35070211328 35680082720 36593840936 36962017280 37763591200 37886067712 38410854400 38573062400 38698164224 39371125760 39560909120 40379410688 40549931848 40957911040 41670169600 42563379200 42737332480 42768550400 43653416960 43805765792 43837764160 44556591104 44600103400 44744752384 45742301170 46202521600 47158435840 47357584640 48337396736 48372705280 49213907200 49373519872 49451136400 50474263360 50687414810 51197388800 51736119944 52256645120 53421665600 54566771200 54757207240 54797205200 55695738880 55930940480 57088132352 58948044800 59196980800 60421745920 60465881600 61716899840 62993801216 63092829200 63297454592 64670149930 65320806400 66672271360 68379731968 68429680640 68446509050 69619673600 69913675600 70140422656 71360165440 73187681872 75527182400 75772135424 77146124800 78742251520 79121818240 80758821376 81099863696 83340339200 85474664960 85537100800 87306833920 87611531584 87675528320 89200206800 89489504768 91484602340 92405043200 94715169280 96674793472 96745410560 98427814400 98902272800 100948526720 101374829620 102394777600 103472239888 106843331200 109133542400 109514414480 109594410400 111391477760 111861880960 114176264704 114355752925 117896089600 118393961600 120843491840 120931763200 123433799680 126185658400 126594909184 126718537025 129340299860 130641612800 136759463936 136859361280 136893018100 139239347200 139827351200 140280845312 142720330880 146375363744 151054364800 151544270848 154292249600 157484503040 158243636480 161517642752 161675374825 162199727392 166680678400 170949329920 171074201600 174613667840 175223063168 175351056640 178400413600 178979009536 182969204680 184810086400 187543434797 189430338560 193349586944 193490821120 196855628800 197804545600 201897053440 202749659240 204789555200 206944479776 213686662400 218267084800 219028828960 219188820800 222782955520 223723761920 228352529408 228711505850 235792179200 236787923200 241686983680 241863526400 246867599360 252371316800 253189818368 253437074050 258680599720 261283225600 273518927872 273786036200 278478694400 279654702400 280561690624 285440661760 292750727488 302108729600 303088541696 308584499200 314969006080 316487272960 323035285504 323350749650 324399454784 333361356800 341898659840 342148403200 350446126336 350702113280 356800827200 357958019072 365938409360 375086869594 378860677120 386699173888 393711257600 395609091200 403794106880 405499318480 413888959552 427373324800 436534169600 438057657920 438377641600 447447523840 456705058816 457423011700 473575846400 483373967360 483727052800 504742633600 506379636736 506874148100 517361199440 547572072400 556957388800 559309404800 561123381248 570881323520 585501454976 604217459200 617168998400 632974545920 646070571008 646701499300 648798909568 683797319680 684296806400 700892252672 701404226560 713601654400 715916038144 731876818720 750173739188 757721354240 787422515200 791218182400 807588213760 810998636960 827777919104 854746649600 873068339200 876115315840 876755283200 894895047680 913410117632 914846023400 937717173985 947151692800 966747934720 967454105600 1009485267200 1012759273472 1013748296200 1034722398880 1095144144800 1113914777600 1118618809600 1122246762496 1141762647040 1171002909952 1208434918400 1234337996800 1265949091840 1292141142016 1293402998600 1297597819136 1367594639360 1401784505344 1402808453120 1427203308800 1431832076288 1463753637440 1500347478376 1515442708480 1574845030400 1582436364800 1615176427520 1621997273920 1655555838208 1709493299200 1752230631680 1753510566400 1789790095360 1826820235264 1829692046800 1875434347970 1894303385600 1933495869440 2018970534400 2027496592400 2069444797760 2190288289600 2237237619200 2283525294080 2342005819904 2416869836800 2531898183680 2586805997200 2595195638272 2803569010688 2805616906240 2854406617600 2927507274880 3000694956752 3164872729600 3230352855040 3243994547840 3311111676416 3418986598400 3504461263360 3507021132800 3579580190720 3659384093600 3750868695940 3788606771200 4037941068800 4054993184800 4138889595520 4380576579200 4474475238400 4567050588160 4684011639808 4688585869925 4833739673600 5063796367360 5173611994400 5190391276544 5607138021376 5611233812480 5708813235200 5855014549760 6001389913504 6329745459200 6460705710080 6487989095680 6622223352832 6837973196800 7008922526720 7014042265600 7159160381440 7318768187200 7501737391880 7577213542400 8075882137600 8109986369600 8277779191040 8761153158400 8948950476800 9134101176320 9368023279616 9377171739850 9667479347200 10347223988800 10380782553088 11214276042752 11417626470400 11710029099520 12002779827008 12659490918400 12975978191360 13244446705664 14017845053440 14028084531200 14637536374400 15003474783760 16151764275200 16219972739200 16555558382080 17522306316800 17897900953600 18736046559232 18754343479700 20694447977600 20761565106176 22835252940800 23420058199040 24005559654016 25318981836800 25951956382720 26488893411328 28035690106880 28056169062400 29275072748800 30006949567520 32303528550400 32439945478400 33111116764160 35044612633600 35795801907200 37472093118464 37508686959400 41388895955200 41523130212352 45670505881600 46840116398080 48011119308032 51903912765440 52977786822656 56071380213760 58550145497600 60013899135040 64879890956800 66222233528320 70089225267200 75017373918800 82777791910400 93680232796160 96022238616064 103807825530880 117100290995200 120027798270080 129759781913600 132444467056640 140178450534400 150034747837600 165555583820800 187360465592320 192044477232128 207615651061760 234200581990400 240055596540160 259519563827200 264888934113280 280356901068800 300069495675200 331111167641600 384088954464256 468401163980800 480111193080320 519039127654400 600138991350400 662222335283200 768177908928512 936802327961600 960222386160640 1038078255308800 1200277982700800 1324444670566400 1536355817857024 1920444772321280 2400555965401600 3840889544642560 4801111930803200 7681779089285120 9602223861606400 19204447723212800 38408895446425600
- Sum of all divisors σ(n): 104619091788484560
- Sum of proper divisors (its aliquot sum) s(n): 66210196342058960
- 38408895446425600 is an abundant number, because the sum of its proper divisors (66210196342058960) is greater than itself. Its abundance is 27801300895633360
Bases of 38408895446425600
- Binary: 100010000111010010101111110110010100110010100000000000002
- Hexadecimal: 0x8874AFD94CA000
- Base-36: AI6TEZ8IBR4
Squares and roots of 38408895446425600
- 38408895446425600 squared (384088954464256002) is 1475243249414453190719816335360000
- 38408895446425600 cubed (384088954464256003) is 56662463724804896850569314383135466602889216000000
-
The
square root of 38408895446425600 is 195981875.3008185705 -
The
cube root of 38408895446425600 is 337399.1151860555
Scales and comparisons
How big is 38408895446425600?- 38,408,895,446,425,600 seconds is equal to 1,221,284,068 years, 35 weeks, 3 days, 7 hours, 6 minutes, 40 seconds.
-
To count from 1 to 38,408,895,446,425,600 would take you about three billion, six hundred sixty-three million, eight hundred fifty-two thousand, two hundred six 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 38408895446425600 cubic inches would be around 28116.6 feet tall.
Recreational maths with 38408895446425600
- 38408895446425600 backwards is 00652464459880483
- The number of decimal digits it has is: 17
- The sum of 38408895446425600's digits is 76
- 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 38408895446425600 - Facts about the integer". Numbermatics.com. 2024. Web. 8 June 2024.
APA style:
Numbermatics. (2024). Number 38408895446425600 - Facts about the integer. Retrieved 8 June 2024, from https://numbermatics.com/n/38408895446425600/
Chicago style:
Numbermatics. 2024. "Number 38408895446425600 - Facts about the integer". https://numbermatics.com/n/38408895446425600/
The information we have on file for 38408895446425600 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 38408895446425600, math, Factors of 38408895446425600, curriculum, school, college, exams, university, Prime factorization of 38408895446425600, STEM, science, technology, engineering, physics, economics, calculator, thirty-eight quadrillion, four hundred eight trillion, eight hundred ninety-five billion, four hundred forty-six million, four hundred twenty-five thousand, six hundred.