What is the Greatest Common Factor of 1239 and 1245?

Greatest common factor (GCF) of 1239 and 1245 is 3.

GCF(1239,1245) = 3

We will now calculate the prime factors of 1239 and 1245, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 1239 and 1245.

How to find the GCF of 1239 and 1245?

We will first find the prime factorization of 1239 and 1245. After we will calculate the factors of 1239 and 1245 and find the biggest common factor number .

Step-1: Prime Factorization of 1239

Prime factors of 1239 are 3, 7, 59. Prime factorization of 1239 in exponential form is:

1239 = 3¹ × 7¹ × 59¹

Step-2: Prime Factorization of 1245

Prime factors of 1245 are 3, 5, 83. Prime factorization of 1245 in exponential form is:

1245 = 3¹ × 5¹ × 83¹

Step-3: Factors of 1239

List of positive integer factors of 1239 that divides 1239 without a remainder.

1, 3, 7, 21, 59, 177, 413

Step-4: Factors of 1245

List of positive integer factors of 1245 that divides 1239 without a remainder.

1, 3, 5, 15, 83, 249, 415

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 1239 and 1245. The biggest common factor number is the GCF number.
So the greatest common factor 1239 and 1245 is 3.

Also check out the Least Common Multiple of 1239 and 1245