What are the divisors of 4178?

1, 2, 2089, 4178

There is a total of 4 positive divisors.
The sum of these divisors is 6270.
The arithmetic mean is 1567.5.

2 even divisors

2, 4178

2 odd divisors

1, 2089

How to compute the divisors of 4178?

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 4178 by each of the numbers from 1 to 4178 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)

4178 / 1 = 4178 (the remainder is 0, so 1 is a divisor of 4178)
4178 / 2 = 2089 (the remainder is 0, so 2 is a divisor of 4178)
4178 / 3 = 1392.6666666667 (the remainder is 2, so 3 is not a divisor of 4178)
...
4178 / 4177 = 1.0002394062724 (the remainder is 1, so 4177 is not a divisor of 4178)
4178 / 4178 = 1 (the remainder is 0, so 4178 is a divisor of 4178)

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 4178 (i.e. 64.637450444769). 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 $\frac{N}{d} = D$ )

4178 / 1 = 4178 (the remainder is 0, so 1 and 4178 are divisors of 4178)
4178 / 2 = 2089 (the remainder is 0, so 2 and 2089 are divisors of 4178)
4178 / 3 = 1392.6666666667 (the remainder is 2, so 3 is not a divisor of 4178)
...
4178 / 63 = 66.31746031746 (the remainder is 20, so 63 is not a divisor of 4178)
4178 / 64 = 65.28125 (the remainder is 18, so 64 is not a divisor of 4178)