What are the divisors of 383?

1, 383

There is a total of 2 positive divisors.
The sum of these divisors is 384.
The arithmetic mean is 192.

2 odd divisors

1, 383

How to compute the divisors of 383?

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 383 by each of the numbers from 1 to 383 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)

383 / 1 = 383 (the remainder is 0, so 1 is a divisor of 383)
383 / 2 = 191.5 (the remainder is 1, so 2 is not a divisor of 383)
383 / 3 = 127.66666666667 (the remainder is 2, so 3 is not a divisor of 383)
...
383 / 382 = 1.0026178010471 (the remainder is 1, so 382 is not a divisor of 383)
383 / 383 = 1 (the remainder is 0, so 383 is a divisor of 383)

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 383 (i.e. 19.570385790781). 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 $\frac{N}{d} = D$ )

383 / 1 = 383 (the remainder is 0, so 1 and 383 are divisors of 383)
383 / 2 = 191.5 (the remainder is 1, so 2 is not a divisor of 383)
383 / 3 = 127.66666666667 (the remainder is 2, so 3 is not a divisor of 383)
...
383 / 18 = 21.277777777778 (the remainder is 5, so 18 is not a divisor of 383)
383 / 19 = 20.157894736842 (the remainder is 3, so 19 is not a divisor of 383)