Coprime checker

Check whether two numbers are coprime — meaning they share no common factor other than 1 (GCD = 1).

Number 1 Number 2

What does coprime mean?

Two numbers are coprime (or relatively prime) if their greatest common divisor is 1. They share no prime factors. Example: 8 and 15 are coprime (GCD=1), but 6 and 9 are not (GCD=3).

Properties of coprime numbers

Consecutive integers are always coprime. Any prime p is coprime to every number it doesn't divide. Euler's totient φ(n) counts numbers 1 to n that are coprime to n.

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