What are the divisors of 9055?

1, 5, 1811, 9055

There is a total of 4 positive divisors.
The sum of these divisors is 10872.
The arithmetic mean is 2718.

4 odd divisors

1, 5, 1811, 9055

How to compute the divisors of 9055?

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 9055 by each of the numbers from 1 to 9055 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)

9055 / 1 = 9055 (the remainder is 0, so 1 is a divisor of 9055)
9055 / 2 = 4527.5 (the remainder is 1, so 2 is not a divisor of 9055)
9055 / 3 = 3018.3333333333 (the remainder is 1, so 3 is not a divisor of 9055)
...
9055 / 9054 = 1.0001104484206 (the remainder is 1, so 9054 is not a divisor of 9055)
9055 / 9055 = 1 (the remainder is 0, so 9055 is a divisor of 9055)

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 9055 (i.e. 95.157763740012). 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 $\frac{N}{d} = D$ )

9055 / 1 = 9055 (the remainder is 0, so 1 and 9055 are divisors of 9055)
9055 / 2 = 4527.5 (the remainder is 1, so 2 is not a divisor of 9055)
9055 / 3 = 3018.3333333333 (the remainder is 1, so 3 is not a divisor of 9055)
...
9055 / 94 = 96.329787234043 (the remainder is 31, so 94 is not a divisor of 9055)
9055 / 95 = 95.315789473684 (the remainder is 30, so 95 is not a divisor of 9055)