What are the divisors of 5080?

1, 2, 4, 5, 8, 10, 20, 40, 127, 254, 508, 635, 1016, 1270, 2540, 5080

12 even divisors

2, 4, 8, 10, 20, 40, 254, 508, 1016, 1270, 2540, 5080

4 odd divisors

1, 5, 127, 635

How to compute the divisors of 5080?

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 5080 by each of the numbers from 1 to 5080 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)

  • 5080 / 1 = 5080 (the remainder is 0, so 1 is a divisor of 5080)
  • 5080 / 2 = 2540 (the remainder is 0, so 2 is a divisor of 5080)
  • 5080 / 3 = 1693.3333333333 (the remainder is 1, so 3 is not a divisor of 5080)
  • ...
  • 5080 / 5079 = 1.0001968891514 (the remainder is 1, so 5079 is not a divisor of 5080)
  • 5080 / 5080 = 1 (the remainder is 0, so 5080 is a divisor of 5080)

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 5080 (i.e. 71.274118724822). 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 )

  • 5080 / 1 = 5080 (the remainder is 0, so 1 and 5080 are divisors of 5080)
  • 5080 / 2 = 2540 (the remainder is 0, so 2 and 2540 are divisors of 5080)
  • 5080 / 3 = 1693.3333333333 (the remainder is 1, so 3 is not a divisor of 5080)
  • ...
  • 5080 / 70 = 72.571428571429 (the remainder is 40, so 70 is not a divisor of 5080)
  • 5080 / 71 = 71.549295774648 (the remainder is 39, so 71 is not a divisor of 5080)