What are the divisors of 1349?

1, 19, 71, 1349

4 odd divisors

1, 19, 71, 1349

How to compute the divisors of 1349?

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 1349 by each of the numbers from 1 to 1349 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)

  • 1349 / 1 = 1349 (the remainder is 0, so 1 is a divisor of 1349)
  • 1349 / 2 = 674.5 (the remainder is 1, so 2 is not a divisor of 1349)
  • 1349 / 3 = 449.66666666667 (the remainder is 2, so 3 is not a divisor of 1349)
  • ...
  • 1349 / 1348 = 1.0007418397626 (the remainder is 1, so 1348 is not a divisor of 1349)
  • 1349 / 1349 = 1 (the remainder is 0, so 1349 is a divisor of 1349)

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 1349 (i.e. 36.728735344414). 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 )

  • 1349 / 1 = 1349 (the remainder is 0, so 1 and 1349 are divisors of 1349)
  • 1349 / 2 = 674.5 (the remainder is 1, so 2 is not a divisor of 1349)
  • 1349 / 3 = 449.66666666667 (the remainder is 2, so 3 is not a divisor of 1349)
  • ...
  • 1349 / 35 = 38.542857142857 (the remainder is 19, so 35 is not a divisor of 1349)
  • 1349 / 36 = 37.472222222222 (the remainder is 17, so 36 is not a divisor of 1349)