What is the Greatest Common Factor of 18 and 216?

Greatest common factor (GCF) of 18 and 216 is 18.

GCF(18,216) = 18

We will now calculate the prime factors of 18 and 216, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 18 and 216.

How to find the GCF of 18 and 216?

We will first find the prime factorization of 18 and 216. After we will calculate the factors of 18 and 216 and find the biggest common factor number .

Step-1: Prime Factorization of 18

Prime factors of 18 are 2, 3. Prime factorization of 18 in exponential form is:

18 = 2¹ × 3²

Step-2: Prime Factorization of 216

Prime factors of 216 are 2, 3. Prime factorization of 216 in exponential form is:

216 = 2³ × 3³

Step-3: Factors of 18

List of positive integer factors of 18 that divides 18 without a remainder.

1, 2, 3, 6, 9

Step-4: Factors of 216

List of positive integer factors of 216 that divides 18 without a remainder.

1, 2, 3, 4, 6, 8, 9, 12, 18, 24, 27, 36, 54, 72, 108

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 18 and 216. The biggest common factor number is the GCF number.
So the greatest common factor 18 and 216 is 18.

Also check out the Least Common Multiple of 18 and 216