GCF for 21 and 54

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

What is the Greatest common Divisor of 21 and 54?

Answer: GCF of 21 and 54 is 3

(Three)

Finding GCF for 21 and 54 using all factors (divisors) listing

The first method to find GCF for numbers 21 and 54 is to list all factors for both numbers and pick the highest common one:

All factors of 21: 1, 3, 7, 21

All factors of 54: 1, 2, 3, 6, 9, 18, 27, 54

So the Greatest Common Factor for 21 and 54 is 3

Finding GCF for 21 and 54 by Prime Factorization

The second method to find GCF for numbers 21 and 54 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 21: 3, 7

All Prime Factors of 54: 2, 3, 3, 3

As we can see there is only one Prime Factor common to both numbers. It is 3

So 3 is the Greatest Common Factor of 21 and 54

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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 21 and 54? (The answer is: 3). Select the first number (e.g. '21') and the second number (e.g. '54'). 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

"Greatest Common Factor" Calculator

Greatest Common Factor of

and

GCF Table

Number 1Number 2GCF
6546
7541
8542
9549
10542
11541
12546
13541
14542
15543
16542
17541
185418
19541
20542
21543
22542
23541
24546
25541
26542
275427
28542
29541
30546
31541
32542
33543
34542
35541

FAQ

What is the Greatest common Divisor of 21 and 54?

GCF of 21 and 54 is 3

See Also