GCF for 20 and 620

What is the Greatest Common Factor of 20 and 620?

Answer: GCF of 20 and 620 is 20

(Twenty)

Finding GCF for 20 and 620 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 620 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 620: 1, 2, 4, 5, 10, 20, 31, 62, 124, 155, 310, 620

So the Greatest Common Factor for 20 and 620 is 20

Finding GCF for 20 and 620 by Prime Factorization

The second method to find GCF for numbers 20 and 620 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 620: 2, 2, 5, 31

As we can see there are Prime Factors common to both numbers: 2, 2, 5

Now we need to multiply them to find GCF: 2 × 2 × 5 = 20

GCF Table

Number 1Number 2GCF
56205
66202
76201
86204
96201
1062010
116201
126204
136201
146202
156205
166204
176201
186202
196201
2062020
216201
226202
236201
246204
256205
266202
276201
286204
296201
3062010
3162031
326204
336201
346202

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 620? (The answer is: 20). Select the first number (e.g. '20') and the second number (e.g. '620'). 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 620?

GCF of 20 and 620 is 20