What is the Greatest Common Factor of 21378 and 21387?

Greatest common factor (GCF) of 21378 and 21387 is 3.

GCF(21378,21387) = 3

We will now calculate the prime factors of 21378 and 21387, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21378 and 21387.

How to find the GCF of 21378 and 21387?

We will first find the prime factorization of 21378 and 21387. After we will calculate the factors of 21378 and 21387 and find the biggest common factor number .

Step-1: Prime Factorization of 21378

Prime factors of 21378 are 2, 3, 7, 509. Prime factorization of 21378 in exponential form is:

21378 = 2¹ × 3¹ × 7¹ × 509¹

Step-2: Prime Factorization of 21387

Prime factors of 21387 are 3, 7129. Prime factorization of 21387 in exponential form is:

21387 = 3¹ × 7129¹

Step-3: Factors of 21378

List of positive integer factors of 21378 that divides 21378 without a remainder.

1, 2, 3, 6, 7, 14, 21, 42, 509, 1018, 1527, 3054, 3563, 7126, 10689

Step-4: Factors of 21387

List of positive integer factors of 21387 that divides 21378 without a remainder.

1, 3, 7129

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21378 and 21387. The biggest common factor number is the GCF number.
So the greatest common factor 21378 and 21387 is 3.

Also check out the Least Common Multiple of 21378 and 21387