What is the Greatest Common Factor of 1242 and 1251?

Greatest common factor (GCF) of 1242 and 1251 is 9.

GCF(1242,1251) = 9

We will now calculate the prime factors of 1242 and 1251, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 1242 and 1251.

How to find the GCF of 1242 and 1251?

We will first find the prime factorization of 1242 and 1251. After we will calculate the factors of 1242 and 1251 and find the biggest common factor number .

Step-1: Prime Factorization of 1242

Prime factors of 1242 are 2, 3, 23. Prime factorization of 1242 in exponential form is:

1242 = 2¹ × 3³ × 23¹

Step-2: Prime Factorization of 1251

Prime factors of 1251 are 3, 139. Prime factorization of 1251 in exponential form is:

1251 = 3² × 139¹

Step-3: Factors of 1242

List of positive integer factors of 1242 that divides 1242 without a remainder.

1, 2, 3, 6, 9, 18, 23, 27, 46, 54, 69, 138, 207, 414, 621

Step-4: Factors of 1251

List of positive integer factors of 1251 that divides 1242 without a remainder.

1, 3, 9, 139, 417

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 1242 and 1251. The biggest common factor number is the GCF number.
So the greatest common factor 1242 and 1251 is 9.

Also check out the Least Common Multiple of 1242 and 1251