# What is a co-prime number?

##### 1 Answer

Apr 6, 2016

Numbers, which do not have any common factor between them other than one, are called co-prime numbers.

#### Explanation:

**When two numbers (they may not be prime) do not have any common factor other than one between them they are called co-prime or relatively prime.**

It is obvious that two prime numbers are always co-prime. For example,

However, even two composite numbers can also be co-prime or relatively prime. For example