21807940

Names of 21807940

• Cardinal: 21807940 can be written as Twenty-one million, eight hundred seven thousand, nine hundred forty.

Scientific notation

• Scientific notation: 2.180794 × 10⁷

Factors of 21807940

• Number of distinct prime factors ω(n): 5
• Total number of prime factors Ω(n): 9
• Sum of prime factors: 42

Divisors of 21807940

• Number of divisors d(n): 144
• Complete list of divisors:
  1 2 4 5 7 10 11 14 17 20 22 28 34 35 44 49 55 68 70 77 85 98 110 119 140 154 170 187 196 220 238 245 289 308 340 343 374 385 476 490 539 578 595 686 748 770 833 935 980 1078 1156 1190 1309 1372 1445 1540 1666 1715 1870 2023 2156 2380 2618 2695 2890 3179 3332 3430 3740 3773 4046 4165 5236 5390 5780 5831 6358 6545 6860 7546 8092 8330 9163 10115 10780 11662 12716 13090 14161 15092 15895 16660 18326 18865 20230 22253 23324 26180 28322 29155 31790 36652 37730 40460 44506 45815 56644 58310 63580 64141 70805 75460 89012 91630 99127 111265 116620 128282 141610 155771 183260 198254 222530 256564 283220 311542 320705 396508 445060 495635 623084 641410 778855 991270 1090397 1282820 1557710 1982540 2180794 3115420 4361588 5451985 10903970 21807940
• Sum of all divisors σ(n): 61891200
• Sum of proper divisors (its aliquot sum) s(n): 40083260
• 21807940 is an abundant number, because the sum of its proper divisors (40083260) is greater than itself. Its abundance is 18275320

Bases of 21807940

• Binary: 1010011001100001101000100₂
• Hexadecimal: 0x14CC344
• Base-36: CZF44

Squares and roots of 21807940

• 21807940 squared (21807940²) is 475586247043600
• 21807940 cubed (21807940³) is 10371556340352006184000
• The square root of 21807940 is 4669.8972151429
• The cube root of 21807940 is 279.3861552499

Scales and comparisons

• 21,807,940 seconds is equal to 36 weeks, 9 hours, 45 minutes, 40 seconds.
• To count from 1 to 21,807,940 would take you about two weeks!

  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 21807940 cubic inches would be around 23.3 feet tall.

Recreational maths with 21807940

• 21807940 backwards is 04970812
• The number of decimal digits it has is: 8
• The sum of 21807940's digits is 31
• More coming soon!