# What type of number has an odd number of factors?

A factor of a number is a number that divides the given number evenly without leaving any remainder.

## Answer: A square number has an odd number of factors

Most of the numbers have an even number of factors except for the square numbers which have an odd number of factors.

## Explanation:

Let's take some examples to understand the number of factors

Factors of 3 = 1, 3 (2 factors)

Factors of 12 = 1, 2, 3, 4, 6, 12 (6 factors)

Factors of 15 = 1, 3, 5, 15 (4 factors)

Thus, we see that the non-square numbers have an even number of factors.

Square numbers are formed by multiplying a number by itself such as 9, 16, 25

All square numbers have an odd number of factors.

Let's take some examples:

Factors of 9: 1, 3, 9 (3 factors)

Factors of 16: 1, 2, 4, 8, 16 (5 factors)

Factors of 25: 1, 5, 25 (3 factors)

### Thus, we see that the square numbers have an odd number of factors

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