6405

Names of 6405

• Cardinal: 6405 can be written as Six thousand, four hundred five.

Scientific notation

• Scientific notation: 6.405 × 10³

Factors of 6405

• Number of distinct prime factors ω(n): 4
• Total number of prime factors Ω(n): 4
• Sum of prime factors: 76

Divisors of 6405

• Number of divisors d(n): 16
• Complete list of divisors:
  1 3 5 7 15 21 35 61 105 183 305 427 915 1281 2135 6405
• Sum of all divisors σ(n): 11904
• Sum of proper divisors (its aliquot sum) s(n): 5499
• 6405 is a deficient number, because the sum of its proper divisors (5499) is less than itself. Its deficiency is 906

Bases of 6405

• Binary: 1100100000101₂
• Hexadecimal: 0x1905
• Base-36: 4XX

Squares and roots of 6405

• 6405 squared (6405²) is 41024025
• 6405 cubed (6405³) is 262758880125
• The square root of 6405 is 80.0312438989
• The cube root of 6405 is 18.5711890643

Scales and comparisons

• 6,405 seconds is equal to 1 hour, 46 minutes, 45 seconds.
• To count from 1 to 6,405 would take you about forty-six 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 6405 cubic inches would be around 1.5 feet tall.

Recreational maths with 6405

• 6405 backwards is 5046
• 6405 is a Harshad number.
• The number of decimal digits it has is: 4
• The sum of 6405's digits is 15
• More coming soon!