GCF for 20 and 505

What is the Greatest Common Factor of 20 and 505?

Answer: GCF of 20 and 505 is 5

(Five)

Finding GCF for 20 and 505 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 505 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 505: 1, 5, 101, 505

So the Greatest Common Factor for 20 and 505 is 5

Finding GCF for 20 and 505 by Prime Factorization

The second method to find GCF for numbers 20 and 505 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 505: 5, 101

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 505

GCF Table

Number 1Number 2GCF
55055
65051
75051
85051
95051
105055
115051
125051
135051
145051
155055
165051
175051
185051
195051
205055
215051
225051
235051
245051
255055
265051
275051
285051
295051
305055
315051
325051
335051
345051

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 Factor of 20 and 505? (The answer is: 5). Select the first number (e.g. '20') and the second number (e.g. '505'). 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 Factor of 20 and 505?

GCF of 20 and 505 is 5