643

Names of 643

• Cardinal: 643 can be written as Six hundred forty-three.

Scientific notation

• Scientific notation: 6.43 × 10²

Factors of 643

• Number of distinct prime factors ω(n): 1
• Total number of prime factors Ω(n): 1
• Sum of prime factors: 643

Divisors of 643

• Number of divisors d(n): 2
• Complete list of divisors:
  1 643
• Sum of all divisors σ(n): 644
• Sum of proper divisors (its aliquot sum) s(n): 1
• 643 is a deficient number, because the sum of its proper divisors (1) is less than itself. Its deficiency is 642

Bases of 643

• Binary: 1010000011₂
• Hexadecimal: 0x283
• Base-36: HV

Squares and roots of 643

• 643 squared (643²) is 413449
• 643 cubed (643³) is 265847707
• The square root of 643 is 25.3574446661
• The cube root of 643 is 8.6311829921

Scales and comparisons

• 643 seconds is equal to 10 minutes, 43 seconds.
• To count from 1 to 643 would take you about five minutes.

  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 643 cubic inches would be around 0.7 feet tall.

Recreational maths with 643

• 643 backwards is 346
• The number of decimal digits it has is: 3
• The sum of 643's digits is 13
• More coming soon!