GCF for 20 and 105

What is the Greatest Common Factor of 20 and 105?

Answer: GCF of 20 and 105 is 5

(Five)

Finding GCF for 20 and 105 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 105 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 105: 1, 3, 5, 7, 15, 21, 35, 105

So the Greatest Common Factor for 20 and 105 is 5

Finding GCF for 20 and 105 by Prime Factorization

The second method to find GCF for numbers 20 and 105 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 105: 3, 5, 7

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 105

GCF Table

Number 1Number 2GCF
51055
61053
71057
81051
91053
101055
111051
121053
131051
141057
1510515
161051
171051
181053
191051
201055
21105
221051
231051
241053
251055
261051
271053
28105
291051
30105
311051
321051
331053
341051

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 105? (The answer is: 5). Select the first number (e.g. '20') and the second number (e.g. '105'). 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 105?

GCF of 20 and 105 is 5