What are the divisors of 9599?

1, 29, 331, 9599

There is a total of 4 positive divisors.
The sum of these divisors is 9960.
The arithmetic mean is 2490.

4 odd divisors

1, 29, 331, 9599

How to compute the divisors of 9599?

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 9599 by each of the numbers from 1 to 9599 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)

9599 / 1 = 9599 (the remainder is 0, so 1 is a divisor of 9599)
9599 / 2 = 4799.5 (the remainder is 1, so 2 is not a divisor of 9599)
9599 / 3 = 3199.6666666667 (the remainder is 2, so 3 is not a divisor of 9599)
...
9599 / 9598 = 1.0001041883726 (the remainder is 1, so 9598 is not a divisor of 9599)
9599 / 9599 = 1 (the remainder is 0, so 9599 is a divisor of 9599)

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 9599 (i.e. 97.974486474796). 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 $\frac{N}{d} = D$ )

9599 / 1 = 9599 (the remainder is 0, so 1 and 9599 are divisors of 9599)
9599 / 2 = 4799.5 (the remainder is 1, so 2 is not a divisor of 9599)
9599 / 3 = 3199.6666666667 (the remainder is 2, so 3 is not a divisor of 9599)
...
9599 / 96 = 99.989583333333 (the remainder is 95, so 96 is not a divisor of 9599)
9599 / 97 = 98.958762886598 (the remainder is 93, so 97 is not a divisor of 9599)