638997645

Names of 638997645

• Cardinal: 638997645 can be written as Six hundred thirty-eight million, nine hundred ninety-seven thousand, six hundred forty-five.

Scientific notation

• Scientific notation: 6.38997645 × 10⁸

Factors of 638997645

• Number of distinct prime factors ω(n): 6
• Total number of prime factors Ω(n): 6
• Sum of prime factors: 15730

Divisors of 638997645

• Number of divisors d(n): 64
• Complete list of divisors:
  1 3 5 11 13 15 19 33 39 55 57 65 95 143 165 195 209 247 285 429 627 715 741 1045 1235 2145 2717 3135 3705 8151 13585 15679 40755 47037 78395 172469 203827 235185 297901 517407 611481 862345 893703 1019135 1489505 2242097 2587035 3057405 3276911 3872713 4468515 6726291 9830733 11210485 11618139 16384555 19363565 33631455 42599843 49153665 58090695 127799529 212999215 638997645
• Sum of all divisors σ(n): 1264435200
• Sum of proper divisors (its aliquot sum) s(n): 625437555
• 638997645 is a deficient number, because the sum of its proper divisors (625437555) is less than itself. Its deficiency is 13560090

Bases of 638997645

• Binary: 100110000101100101010010001101₂
• Hexadecimal: 0x2616548D
• Base-36: AKFXQL

Squares and roots of 638997645

• 638997645 squared (638997645²) is 408317990315546025
• 638997645 cubed (638997645³) is 260914234222766716864111125
• The square root of 638997645 is 25278.4027383061
• The cube root of 638997645 is 861.3237433549

Scales and comparisons

• 638,997,645 seconds is equal to 20 years, 16 weeks, 3 days, 19 hours, 20 minutes, 45 seconds.
• To count from 1 to 638,997,645 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 638997645 cubic inches would be around 71.8 feet tall.

Recreational maths with 638997645

• 638997645 backwards is 546799836
• 638997645 is a Harshad number.
• The number of decimal digits it has is: 9
• The sum of 638997645's digits is 57
• More coming soon!