21385728

Names of 21385728

• Cardinal: 21385728 can be written as Twenty-one million, three hundred eighty-five thousand, seven hundred twenty-eight.

Scientific notation

• Scientific notation: 2.1385728 × 10⁷

Factors of 21385728

• Number of distinct prime factors ω(n): 5
• Total number of prime factors Ω(n): 15
• Sum of prime factors: 42

Divisors of 21385728

• Number of divisors d(n): 320
• Complete list of divisors:
  1 2 3 4 6 7 8 9 12 13 14 16 17 18 21 24 26 27 28 32 34 36 39 42 48 51 52 54 56 63 64 68 72 78 84 91 96 102 104 108 112 117 119 126 128 136 144 153 156 168 182 189 192 204 208 216 221 224 234 238 252 256 272 273 288 306 312 336 351 357 364 378 384 408 416 432 442 448 459 468 476 504 512 544 546 576 612 624 663 672 702 714 728 756 768 816 819 832 864 884 896 918 936 952 1008 1071 1088 1092 1152 1224 1248 1326 1344 1404 1428 1456 1512 1536 1547 1632 1638 1664 1728 1768 1792 1836 1872 1904 1989 2016 2142 2176 2184 2304 2448 2457 2496 2652 2688 2808 2856 2912 3024 3094 3213 3264 3276 3328 3456 3536 3584 3672 3744 3808 3978 4032 4284 4352 4368 4608 4641 4896 4914 4992 5304 5376 5616 5712 5824 5967 6048 6188 6426 6528 6552 6656 6912 7072 7344 7488 7616 7956 8064 8568 8704 8736 9282 9792 9828 9984 10608 10752 11232 11424 11648 11934 12096 12376 12852 13056 13104 13824 13923 14144 14688 14976 15232 15912 16128 17136 17472 18564 19584 19656 19968 21216 22464 22848 23296 23868 24192 24752 25704 26112 26208 27846 28288 29376 29952 30464 31824 32256 34272 34944 37128 39168 39312 41769 42432 44928 45696 46592 47736 48384 49504 51408 52416 55692 56576 58752 59904 60928 63648 68544 69888 74256 78336 78624 83538 84864 89856 91392 95472 96768 99008 102816 104832 111384 113152 117504 127296 137088 139776 148512 157248 167076 169728 179712 182784 190944 198016 205632 209664 222768 235008 254592 274176 297024 314496 334152 339456 381888 396032 411264 419328 445536 509184 548352 594048 628992 668304 763776 792064 822528 891072 1018368 1188096 1257984 1336608 1527552 1645056 1782144 2376192 2673216 3055104 3564288 5346432 7128576 10692864 21385728
• Sum of all divisors σ(n): 82494720
• Sum of proper divisors (its aliquot sum) s(n): 61108992
• 21385728 is an abundant number, because the sum of its proper divisors (61108992) is greater than itself. Its abundance is 39723264

Bases of 21385728

• Binary: 1010001100101001000000000₂
• Hexadecimal: 0x1465200
• Base-36: CQDC0

Squares and roots of 21385728

• 21385728 squared (21385728²) is 457349362089984
• 21385728 cubed (21385728³) is 9780749058629909348352
• The square root of 21385728 is 4624.4705642917
• The cube root of 21385728 is 277.5713768183

Scales and comparisons

• 21,385,728 seconds is equal to 35 weeks, 2 days, 12 hours, 28 minutes, 48 seconds.
• To count from 1 to 21,385,728 would take you about six hours!

  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 21385728 cubic inches would be around 23.1 feet tall.

Recreational maths with 21385728

• 21385728 backwards is 82758312
• 21385728 is a Harshad number.
• The number of decimal digits it has is: 8
• The sum of 21385728's digits is 36
• More coming soon!