21457921

Names of 21457921

• Cardinal: 21457921 can be written as Twenty-one million, four hundred fifty-seven thousand, nine hundred twenty-one.

Scientific notation

• Scientific notation: 2.1457921 × 10⁷

Factors of 21457921

• Number of distinct prime factors ω(n): 2
• Total number of prime factors Ω(n): 2
• Sum of prime factors: 692222

Divisors of 21457921

• Number of divisors d(n): 4
• Complete list of divisors:
  1 31 692191 21457921
• Sum of all divisors σ(n): 22150144
• Sum of proper divisors (its aliquot sum) s(n): 692223
• 21457921 is a deficient number, because the sum of its proper divisors (692223) is less than itself. Its deficiency is 20765698

Bases of 21457921

• Binary: 1010001110110110000000001₂
• Hexadecimal: 0x1476C01
• Base-36: CRX1D

Squares and roots of 21457921

• 21457921 squared (21457921²) is 460442373642241
• 21457921 cubed (21457921³) is 9880136078667689640961
• The square root of 21457921 is 4632.2695301547
• The cube root of 21457921 is 277.8833637659

Scales and comparisons

• 21,457,921 seconds is equal to 35 weeks, 3 days, 8 hours, 32 minutes, 1 second.
• To count from 1 to 21,457,921 would take you about twelve 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 21457921 cubic inches would be around 23.2 feet tall.

Recreational maths with 21457921

• 21457921 backwards is 12975412
• 21457921 is a Harshad number.
• The number of decimal digits it has is: 8
• The sum of 21457921's digits is 31
• More coming soon!