21989

Names of 21989

• Cardinal: 21989 can be written as Twenty-one thousand, nine hundred eighty-nine.

Scientific notation

• Scientific notation: 2.1989 × 10⁴

Factors of 21989

• Number of distinct prime factors ω(n): 2
• Total number of prime factors Ω(n): 2
• Sum of prime factors: 2010

Divisors of 21989

• Number of divisors d(n): 4
• Complete list of divisors:
  1 11 1999 21989
• Sum of all divisors σ(n): 24000
• Sum of proper divisors (its aliquot sum) s(n): 2011
• 21989 is a deficient number, because the sum of its proper divisors (2011) is less than itself. Its deficiency is 19978

Bases of 21989

• Binary: 101010111100101₂
• Hexadecimal: 0x55E5
• Base-36: GYT

Squares and roots of 21989

• 21989 squared (21989²) is 483516121
• 21989 cubed (21989³) is 10632035984669
• The square root of 21989 is 148.2868841131
• The cube root of 21989 is 28.0157224625

Scales and comparisons

• 21,989 seconds is equal to 6 hours, 6 minutes, 29 seconds.
• To count from 1 to 21,989 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 21989 cubic inches would be around 2.3 feet tall.

Recreational maths with 21989

• 21989 backwards is 98912
• The number of decimal digits it has is: 5
• The sum of 21989's digits is 29
• More coming soon!