81315391872

Names of 81315391872

• Cardinal: 81315391872 can be written as Eighty-one billion, three hundred fifteen million, three hundred ninety-one thousand, eight hundred seventy-two.

Scientific notation

• Scientific notation: 8.1315391872 × 10¹⁰

Factors of 81315391872

• Number of distinct prime factors ω(n): 6
• Total number of prime factors Ω(n): 13
• Sum of prime factors: 1439

Divisors of 81315391872

• Number of divisors d(n): 384
• Complete list of divisors:
  1 2 3 4 6 8 11 12 13 16 22 24 26 32 33 39 44 48 52 64 66 78 88 96 103 104 121 128 132 143 156 176 192 206 208 242 264 286 309 312 352 363 384 412 416 429 484 528 572 618 624 704 726 824 832 858 968 1056 1133 1144 1236 1248 1307 1339 1408 1452 1573 1648 1664 1716 1936 2112 2266 2288 2472 2496 2614 2678 2904 3146 3296 3399 3432 3872 3921 4017 4224 4532 4576 4719 4944 4992 5228 5356 5808 6292 6592 6798 6864 7744 7842 8034 9064 9152 9438 9888 10456 10712 11616 12463 12584 13184 13596 13728 14377 14729 15488 15684 16068 16991 18128 18304 18876 19776 20912 21424 23232 24926 25168 27192 27456 28754 29458 31368 32136 33982 36256 37389 37752 39552 41824 42848 43131 44187 46464 49852 50336 50973 54384 54912 57508 58916 62736 64272 67964 72512 74778 75504 83648 85696 86262 88374 99704 100672 101946 108768 115016 117832 125472 128544 134621 135928 145024 149556 151008 158147 162019 167296 171392 172524 176748 186901 199408 201344 203892 217536 230032 235664 250944 257088 269242 271856 299112 302016 316294 324038 345048 353496 373802 398816 403863 407784 435072 460064 471328 474441 486057 501888 514176 538484 543712 560703 598224 604032 632588 648076 690096 706992 747604 797632 807726 815568 920128 942656 948882 972114 1076968 1087424 1121406 1196448 1265176 1296152 1380192 1413984 1480831 1495208 1595264 1615452 1631136 1750073 1840256 1885312 1897764 1944228 2055911 2153936 2174848 2242812 2392896 2530352 2592304 2760384 2827968 2961662 2990416 3230904 3262272 3500146 3795528 3888456 4111822 4307872 4442493 4485624 4785792 5060704 5184608 5250219 5520768 5655936 5923324 5980832 6167733 6461808 6524544 7000292 7591056 7776912 8223644 8615744 8884986 8971248 10121408 10369216 10500438 11846648 11961664 12335466 12923616 14000584 15182112 15553824 16289141 16447288 17231488 17769972 17942496 19250803 20242816 20738432 21000876 23693296 23923328 24670932 25847232 28001168 30364224 31107648 32578282 32894576 35539944 35884992 38501606 42001752 47386592 48867423 49341864 51694464 56002336 57752409 60728448 62215296 65156564 65789152 71079888 71769984 77003212 84003504 94773184 97734846 98683728 112004672 115504818 130313128 131578304 142159776 154006424 168007008 189546368 195469692 197367456 211758833 224009344 231009636 260626256 263156608 284319552 308012848 336014016 390939384 394734912 423517666 462019272 521252512 568639104 616025696 635276499 672028032 781878768 789469824 847035332 924038544 1042505024 1232051392 1270552998 1563757536 1694070664 1848077088 2085010048 2464102784 2541105996 3127515072 3388141328 3696154176 5082211992 6255030144 6776282656 7392308352 10164423984 13552565312 20328847968 27105130624 40657695936 81315391872
• Sum of all divisors σ(n): 258357415680
• Sum of proper divisors (its aliquot sum) s(n): 177042023808
• 81315391872 is an abundant number, because the sum of its proper divisors (177042023808) is greater than itself. Its abundance is 95726631936

Bases of 81315391872

• Binary: 1001011101110110001100110100110000000₂
• Hexadecimal: 0x12EEC66980
• Base-36: 11CT31XC

Squares and roots of 81315391872

• 81315391872 squared (81315391872²) is 6612192955296923664384
• 81315391872 cubed (81315391872³) is 537673061293247125885455169486848
• The square root of 81315391872 is 285158.5381362445
• The cube root of 81315391872 is 4332.3571637731

Scales and comparisons

• 81,315,391,872 seconds is equal to 2,585 years, 30 weeks, 8 hours, 51 minutes, 12 seconds.
• To count from 1 to 81,315,391,872 would take you about five thousand, one hundred seventy-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 81315391872 cubic inches would be around 361 feet tall.

Recreational maths with 81315391872

• 81315391872 backwards is 27819351318
• 81315391872 is a Harshad number.
• The number of decimal digits it has is: 11
• The sum of 81315391872's digits is 48
• More coming soon!