What are the divisors of 2528?

1, 2, 4, 8, 16, 32, 79, 158, 316, 632, 1264, 2528

10 even divisors

2, 4, 8, 16, 32, 158, 316, 632, 1264, 2528

2 odd divisors

1, 79

How to compute the divisors of 2528?

A number N is said to be divisible by a number M (with M non-zero) if, when we divide N by M, the remainder of the division is zero.

N mod M = 0

Brute force algorithm

We could start by using a brute-force method which would involve dividing 2528 by each of the numbers from 1 to 2528 to determine which ones have a remainder equal to 0.

Remainder = N ( M × N M )

(where N M is the integer part of the quotient)

  • 2528 / 1 = 2528 (the remainder is 0, so 1 is a divisor of 2528)
  • 2528 / 2 = 1264 (the remainder is 0, so 2 is a divisor of 2528)
  • 2528 / 3 = 842.66666666667 (the remainder is 2, so 3 is not a divisor of 2528)
  • ...
  • 2528 / 2527 = 1.0003957261575 (the remainder is 1, so 2527 is not a divisor of 2528)
  • 2528 / 2528 = 1 (the remainder is 0, so 2528 is a divisor of 2528)

Improved algorithm using square-root

However, there is another slightly better approach that reduces the number of iterations by testing only integers less than or equal to the square root of 2528 (i.e. 50.279220359906). Indeed, if a number N has a divisor D greater than its square root, then there is necessarily a smaller divisor d such that:

D × d = N

(thus, if N D = d , then N d = D )

  • 2528 / 1 = 2528 (the remainder is 0, so 1 and 2528 are divisors of 2528)
  • 2528 / 2 = 1264 (the remainder is 0, so 2 and 1264 are divisors of 2528)
  • 2528 / 3 = 842.66666666667 (the remainder is 2, so 3 is not a divisor of 2528)
  • ...
  • 2528 / 49 = 51.591836734694 (the remainder is 29, so 49 is not a divisor of 2528)
  • 2528 / 50 = 50.56 (the remainder is 28, so 50 is not a divisor of 2528)