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Table of divisors

The tables below list all of the divisors of the numbers 1 to 1000.

A divisor of an integer n is an integer m, for which is again an integer (which is necessarily also a divisor of n). For example, 3 is a divisor of 21, since = 3 (and therefore 7 is also a divisor of 21).

If m is a divisor of n, then so is −m. The tables below only list positive divisors.

Key to the tables

  • d(n) is the number of the positive divisors of n, including 1 and n itself
  • σ(n) is the sum of the positive divisors of n, including 1 and n itself
  • s(n) is the sum of the proper divisors of n, including 1 but not n itself; that is, s(n) = ÃÂƒ(n) − n
  • a deficient number is greater than the sum of its proper divisors; that is, s(n)&nbsp;<&nbsp;n
  • a perfect number equals the sum of its proper divisors; that is, s(n)&nbsp;=&nbsp;n
  • an abundant number is lesser than the sum of its proper divisors; that is, s(n)&nbsp;>&nbsp;n
  • a highly abundant number has a sum of positive divisors that is greater than any lesser number; that is, σ(n) > σ(m) for every positive integer m < n. Counterintuitively, the first seven highly abundant numbers (as well as the ninth) are not abundant numbers.
  • a prime number has only 1 and itself as divisors; that is, d(n)&nbsp;=&nbsp;2
  • a composite number has more than just 1 and itself as divisors; that is, d(n)&nbsp;>&nbsp;2
  • a highly composite number has a number of positive divisors that is greater than any lesser number; that is, d(n) > d(m) for every positive integer m < n. Counterintuitively, the first two highly composite numbers are not composite numbers.
  • a superior highly composite number has a ratio between its number of divisors and itself raised to some positive power that equals or is greater than the ratio of any other number; that is, there exists some ε such that for every other positive integer m
  • a primitive abundant number is an abundant number whose proper divisors are all deficient numbers
  • a weird number is a number that is abundant but not semiperfect; that is, no subset of the proper divisors of n sum to n

1 to 100

101 to 200

201 to 300

301 to 400

401 to 500

501 to 600

601 to 700

701 to 800

801 to 900

901 to 1000

Sortable 1-1000

See also

External links