GCF for 18 and 72

What is the Greatest common Divisor of 18 and 72?

Answer: GCF of 18 and 72 is 18

(Eighteen)

Finding GCF for 18 and 72 using all factors (divisors) listing

The first method to find GCF for numbers 18 and 72 is to list all factors for both numbers and pick the highest common one:

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

All factors of 72: 1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 36, 72

So the Greatest Common Factor for 18 and 72 is 18

Finding GCF for 18 and 72 by Prime Factorization

The second method to find GCF for numbers 18 and 72 is to list all Prime Factors for both numbers and multiply the common ones:

All Prime Factors of 18: 2, 3, 3

All Prime Factors of 72: 2, 2, 2, 3, 3

As we can see there are Prime Factors common to both numbers: 2, 3, 3

Now we need to multiply them to find GCF: 2 × 3 × 3 = 18

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 18 and 72? (The answer is: 18). Select the first number (e.g. '18') and the second number (e.g. '72'). 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

GCF Table

Number 1Number 2GCF
3723
4724
5721
6726
7721
872
972
10722
11721
1272
13721
14722
15723
1672
17721
1872
19721
2072
21723
22722
23721
2472
25721
26722
2772
2872
29721
3072
31721
3272

FAQ

What is the Greatest common Divisor of 18 and 72?

GCF of 18 and 72 is 18