What is the Greatest Common Factor of 21420 and 21439?

Greatest common factor (GCF) of 21420 and 21439 is 1.

GCF(21420,21439) = 1

We will now calculate the prime factors of 21420 and 21439, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21420 and 21439.

How to find the GCF of 21420 and 21439?

We will first find the prime factorization of 21420 and 21439. After we will calculate the factors of 21420 and 21439 and find the biggest common factor number .

Step-1: Prime Factorization of 21420

Prime factors of 21420 are 2, 3, 5, 7, 17. Prime factorization of 21420 in exponential form is:

21420 = 2² × 3² × 5¹ × 7¹ × 17¹

Step-2: Prime Factorization of 21439

Prime factors of 21439 are 11, 1949. Prime factorization of 21439 in exponential form is:

21439 = 11¹ × 1949¹

Step-3: Factors of 21420

List of positive integer factors of 21420 that divides 21420 without a remainder.

1, 2, 3, 4, 5, 6, 7, 9, 10, 12, 14, 15, 17, 18, 20, 21, 28, 30, 34, 35, 36, 42, 45, 51, 60, 63, 68, 70, 84, 85, 90, 102, 105, 119, 126, 140, 153, 170, 180, 204, 210, 238, 252, 255, 306, 315, 340, 357, 420, 476, 510, 595, 612, 630, 714, 765, 1020, 1071, 1190, 1260, 1428, 1530, 1785, 2142, 2380, 3060, 3570, 4284, 5355, 7140, 10710

Step-4: Factors of 21439

List of positive integer factors of 21439 that divides 21420 without a remainder.

1, 11, 1949

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21420 and 21439. The biggest common factor number is the GCF number.
So the greatest common factor 21420 and 21439 is 1.

Also check out the Least Common Multiple of 21420 and 21439