What are the divisors of 3935?

1, 5, 787, 3935

There is a total of 4 positive divisors.
The sum of these divisors is 4728.
The arithmetic mean is 1182.

4 odd divisors

1, 5, 787, 3935

How to compute the divisors of 3935?

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 3935 by each of the numbers from 1 to 3935 to determine which ones have a remainder equal to 0.

$Remainder = N - (M \times ⌊ \frac{N}{M} ⌋)$

(where $⌊ \frac{N}{M} ⌋$ is the integer part of the quotient)

3935 / 1 = 3935 (the remainder is 0, so 1 is a divisor of 3935)
3935 / 2 = 1967.5 (the remainder is 1, so 2 is not a divisor of 3935)
3935 / 3 = 1311.6666666667 (the remainder is 2, so 3 is not a divisor of 3935)
...
3935 / 3934 = 1.0002541942044 (the remainder is 1, so 3934 is not a divisor of 3935)
3935 / 3935 = 1 (the remainder is 0, so 3935 is a divisor of 3935)

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 3935 (i.e. 62.729578350249). Indeed, if a number N has a divisor D greater than its square root, then there is necessarily a smaller divisor d such that:

$D \times d = N$

(thus, if $\frac{N}{D} = d$ , then $\frac{N}{d} = D$ )

3935 / 1 = 3935 (the remainder is 0, so 1 and 3935 are divisors of 3935)
3935 / 2 = 1967.5 (the remainder is 1, so 2 is not a divisor of 3935)
3935 / 3 = 1311.6666666667 (the remainder is 2, so 3 is not a divisor of 3935)
...
3935 / 61 = 64.508196721311 (the remainder is 31, so 61 is not a divisor of 3935)
3935 / 62 = 63.467741935484 (the remainder is 29, so 62 is not a divisor of 3935)