645020820

Names of 645020820

• Cardinal: 645020820 can be written as Six hundred forty-five million, twenty thousand, eight hundred twenty.

Scientific notation

• Scientific notation: 6.4502082 × 10⁸

Factors of 645020820

• Number of distinct prime factors ω(n): 4
• Total number of prime factors Ω(n): 9
• Sum of prime factors: 641

Divisors of 645020820

• Number of divisors d(n): 90
• Complete list of divisors:
  1 2 3 4 5 6 9 10 12 15 18 20 27 30 36 45 54 60 81 90 108 135 162 180 270 324 405 540 631 810 1262 1620 1893 2524 3155 3786 5679 6310 7572 9465 11358 12620 17037 18930 22716 28395 34074 37860 51111 56790 68148 85185 102222 113580 170370 204444 255555 340740 398161 511110 796322 1022220 1194483 1592644 1990805 2388966 3583449 3981610 4777932 5972415 7166898 7963220 10750347 11944830 14333796 17917245 21500694 23889660 32251041 35834490 43001388 53751735 64502082 71668980 107503470 129004164 161255205 215006940 322510410 645020820
• Sum of all divisors σ(n): 2026666026
• Sum of proper divisors (its aliquot sum) s(n): 1381645206
• 645020820 is an abundant number, because the sum of its proper divisors (1381645206) is greater than itself. Its abundance is 736624386

Bases of 645020820

• Binary: 100110011100100011110010010100₂
• Hexadecimal: 0x26723C94
• Base-36: AO1190

Squares and roots of 645020820

• 645020820 squared (645020820²) is 416051858233472400
• 645020820 cubed (645020820³) is 268362110760278118895368000
• The square root of 645020820 is 25397.2600884427
• The cube root of 645020820 is 864.0215561751

Scales and comparisons

• 645,020,820 seconds is equal to 20 years, 26 weeks, 3 days, 12 hours, 27 minutes.
• To count from 1 to 645,020,820 would take you about thirty 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 645020820 cubic inches would be around 72 feet tall.

Recreational maths with 645020820

• 645020820 backwards is 028020546
• 645020820 is a Harshad number.
• The number of decimal digits it has is: 9
• The sum of 645020820's digits is 27
• More coming soon!