GCF for 20 and 665

What is the Greatest common Divisor of 20 and 665?

Answer: GCF of 20 and 665 is 5

(Five)

Finding GCF for 20 and 665 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 665 is to list all factors for both numbers and pick the highest common one:

All factors of 20: 1, 2, 4, 5, 10, 20

All factors of 665: 1, 5, 7, 19, 35, 95, 133, 665

So the Greatest Common Factor for 20 and 665 is 5

Finding GCF for 20 and 665 by Prime Factorization

The second method to find GCF for numbers 20 and 665 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 20: 2, 2, 5

All Prime Factors of 665: 5, 7, 19

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 20 and 665

GCF Table

Number 1Number 2GCF
56655
66651
76657
86651
96651
106655
116651
126651
136651
146657
156655
166651
176651
186651
1966519
206655
216657
226651
236651
246651
256655
266651
276651
286657
296651
306655
316651
326651
336651
346651

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 20 and 665? (The answer is: 5). Select the first number (e.g. '20') and the second number (e.g. '665'). 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 20 and 665?

GCF of 20 and 665 is 5