What is the Greatest Common Factor of 243 and 249?

Greatest common factor (GCF) of 243 and 249 is 3.

GCF(243,249) = 3

We will now calculate the prime factors of 243 and 249, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 243 and 249.

How to find the GCF of 243 and 249?

We will first find the prime factorization of 243 and 249. After we will calculate the factors of 243 and 249 and find the biggest common factor number .

Step-1: Prime Factorization of 243

Prime factors of 243 are 3. Prime factorization of 243 in exponential form is:

243 = 3⁵

Step-2: Prime Factorization of 249

Prime factors of 249 are 3, 83. Prime factorization of 249 in exponential form is:

249 = 3¹ × 83¹

Step-3: Factors of 243

List of positive integer factors of 243 that divides 243 without a remainder.

1, 3, 9, 27, 81

Step-4: Factors of 249

List of positive integer factors of 249 that divides 243 without a remainder.

1, 3, 83

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 243 and 249. The biggest common factor number is the GCF number.
So the greatest common factor 243 and 249 is 3.

Also check out the Least Common Multiple of 243 and 249