What is the Greatest Common Factor of 21240 and 21258?

Greatest common factor (GCF) of 21240 and 21258 is 18.

GCF(21240,21258) = 18

We will now calculate the prime factors of 21240 and 21258, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21240 and 21258.

How to find the GCF of 21240 and 21258?

We will first find the prime factorization of 21240 and 21258. After we will calculate the factors of 21240 and 21258 and find the biggest common factor number .

Step-1: Prime Factorization of 21240

Prime factors of 21240 are 2, 3, 5, 59. Prime factorization of 21240 in exponential form is:

21240 = 2³ × 3² × 5¹ × 59¹

Step-2: Prime Factorization of 21258

Prime factors of 21258 are 2, 3, 1181. Prime factorization of 21258 in exponential form is:

21258 = 2¹ × 3² × 1181¹

Step-3: Factors of 21240

List of positive integer factors of 21240 that divides 21240 without a remainder.

1, 2, 3, 4, 5, 6, 8, 9, 10, 12, 15, 18, 20, 24, 30, 36, 40, 45, 59, 60, 72, 90, 118, 120, 177, 180, 236, 295, 354, 360, 472, 531, 590, 708, 885, 1062, 1180, 1416, 1770, 2124, 2360, 2655, 3540, 4248, 5310, 7080, 10620

Step-4: Factors of 21258

List of positive integer factors of 21258 that divides 21240 without a remainder.

1, 2, 3, 6, 9, 18, 1181, 2362, 3543, 7086, 10629

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21240 and 21258. The biggest common factor number is the GCF number.
So the greatest common factor 21240 and 21258 is 18.

Also check out the Least Common Multiple of 21240 and 21258