What are the divisors of 4207?

1, 7, 601, 4207

There is a total of 4 positive divisors.
The sum of these divisors is 4816.
The arithmetic mean is 1204.

4 odd divisors

1, 7, 601, 4207

How to compute the divisors of 4207?

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 4207 by each of the numbers from 1 to 4207 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)

4207 / 1 = 4207 (the remainder is 0, so 1 is a divisor of 4207)
4207 / 2 = 2103.5 (the remainder is 1, so 2 is not a divisor of 4207)
4207 / 3 = 1402.3333333333 (the remainder is 1, so 3 is not a divisor of 4207)
...
4207 / 4206 = 1.0002377555873 (the remainder is 1, so 4206 is not a divisor of 4207)
4207 / 4207 = 1 (the remainder is 0, so 4207 is a divisor of 4207)

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 4207 (i.e. 64.861390672726). 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 $\frac{N}{d} = D$ )

4207 / 1 = 4207 (the remainder is 0, so 1 and 4207 are divisors of 4207)
4207 / 2 = 2103.5 (the remainder is 1, so 2 is not a divisor of 4207)
4207 / 3 = 1402.3333333333 (the remainder is 1, so 3 is not a divisor of 4207)
...
4207 / 63 = 66.777777777778 (the remainder is 49, so 63 is not a divisor of 4207)
4207 / 64 = 65.734375 (the remainder is 47, so 64 is not a divisor of 4207)