What are the divisors of 2874?

1, 2, 3, 6, 479, 958, 1437, 2874

There is a total of 8 positive divisors.
The sum of these divisors is 5760.
The arithmetic mean is 720.

4 even divisors

2, 6, 958, 2874

4 odd divisors

1, 3, 479, 1437

How to compute the divisors of 2874?

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 2874 by each of the numbers from 1 to 2874 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)

2874 / 1 = 2874 (the remainder is 0, so 1 is a divisor of 2874)
2874 / 2 = 1437 (the remainder is 0, so 2 is a divisor of 2874)
2874 / 3 = 958 (the remainder is 0, so 3 is a divisor of 2874)
...
2874 / 2873 = 1.0003480682214 (the remainder is 1, so 2873 is not a divisor of 2874)
2874 / 2874 = 1 (the remainder is 0, so 2874 is a divisor of 2874)

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 2874 (i.e. 53.609700614721). 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 $\frac{N}{d} = D$ )

2874 / 1 = 2874 (the remainder is 0, so 1 and 2874 are divisors of 2874)
2874 / 2 = 1437 (the remainder is 0, so 2 and 1437 are divisors of 2874)
2874 / 3 = 958 (the remainder is 0, so 3 and 958 are divisors of 2874)
...
2874 / 52 = 55.269230769231 (the remainder is 14, so 52 is not a divisor of 2874)
2874 / 53 = 54.22641509434 (the remainder is 12, so 53 is not a divisor of 2874)