GCF for 80 and 645

What is the Greatest common Divisor of 80 and 645?

Answer: GCF of 80 and 645 is 5

(Five)

Finding GCF for 80 and 645 using all factors (divisors) listing

The first method to find GCF for numbers 80 and 645 is to list all factors for both numbers and pick the highest common one:

All factors of 80: 1, 2, 4, 5, 8, 10, 16, 20, 40, 80

All factors of 645: 1, 3, 5, 15, 43, 129, 215, 645

So the Greatest Common Factor for 80 and 645 is 5

Finding GCF for 80 and 645 by Prime Factorization

The second method to find GCF for numbers 80 and 645 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 80: 2, 2, 2, 2, 5

All Prime Factors of 645: 3, 5, 43

As we can see there is only one Prime Factor common to both numbers. It is 5

So 5 is the Greatest Common Factor of 80 and 645

GCF Table

Number 1Number 2GCF
656455
666453
676451
686451
696453
706455
716451
726453
736451
746451
7564515
766451
776451
786453
796451
806455
816453
826451
836451
846453
856455
8664543
876453
886451
896451
9064515
916451
926451
936453
946451

About "Greatest Common Factor" Calculator

This calculator will help you find the greatest common factor (GCF) of two numbers. For example, it can help you find out what is the Greatest common Divisor of 80 and 645? (The answer is: 5). Select the first number (e.g. '80') and the second number (e.g. '645'). After that hit the 'Calculate' button.
Greatest Common Factor (GCF) also known as the Greatest Common Divisor (GCD) or Highest Common Factor (HCF) - it is the largest positive integer that divides each of the integers with zero remainder

FAQ

What is the Greatest common Divisor of 80 and 645?

GCF of 80 and 645 is 5