GCF for 20 and 255

What is the Greatest common Divisor of 20 and 255?

Answer: GCF of 20 and 255 is 5

(Five)

Finding GCF for 20 and 255 using all factors (divisors) listing

The first method to find GCF for numbers 20 and 255 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 255: 1, 3, 5, 15, 17, 51, 85, 255

So the Greatest Common Factor for 20 and 255 is 5

Finding GCF for 20 and 255 by Prime Factorization

The second method to find GCF for numbers 20 and 255 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 255: 3, 5, 17

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 255

GCF Table

Number 1Number 2GCF
52555
62553
72551
82551
92553
102555
112551
122553
132551
142551
1525515
162551
1725517
182553
192551
202555
212553
222551
232551
242553
252555
262551
272553
282551
292551
3025515
312551
322551
332553
3425517

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 255? (The answer is: 5). Select the first number (e.g. '20') and the second number (e.g. '255'). 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 255?

GCF of 20 and 255 is 5