What are the divisors of 3320?

1, 2, 4, 5, 8, 10, 20, 40, 83, 166, 332, 415, 664, 830, 1660, 3320

There is a total of 16 positive divisors.
The sum of these divisors is 7560.
The arithmetic mean is 472.5.

12 even divisors

2, 4, 8, 10, 20, 40, 166, 332, 664, 830, 1660, 3320

4 odd divisors

1, 5, 83, 415

How to compute the divisors of 3320?

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 3320 by each of the numbers from 1 to 3320 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)

3320 / 1 = 3320 (the remainder is 0, so 1 is a divisor of 3320)
3320 / 2 = 1660 (the remainder is 0, so 2 is a divisor of 3320)
3320 / 3 = 1106.6666666667 (the remainder is 2, so 3 is not a divisor of 3320)
...
3320 / 3319 = 1.000301295571 (the remainder is 1, so 3319 is not a divisor of 3320)
3320 / 3320 = 1 (the remainder is 0, so 3320 is a divisor of 3320)

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 3320 (i.e. 57.619441163552). 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 $\frac{N}{d} = D$ )

3320 / 1 = 3320 (the remainder is 0, so 1 and 3320 are divisors of 3320)
3320 / 2 = 1660 (the remainder is 0, so 2 and 1660 are divisors of 3320)
3320 / 3 = 1106.6666666667 (the remainder is 2, so 3 is not a divisor of 3320)
...
3320 / 56 = 59.285714285714 (the remainder is 16, so 56 is not a divisor of 3320)
3320 / 57 = 58.245614035088 (the remainder is 14, so 57 is not a divisor of 3320)