What is the Greatest Common Factor of 21805 and 21818?

Greatest common factor (GCF) of 21805 and 21818 is 1.

GCF(21805,21818) = 1

We will now calculate the prime factors of 21805 and 21818, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21805 and 21818.

How to find the GCF of 21805 and 21818?

We will first find the prime factorization of 21805 and 21818. After we will calculate the factors of 21805 and 21818 and find the biggest common factor number .

Step-1: Prime Factorization of 21805

Prime factors of 21805 are 5, 7, 89. Prime factorization of 21805 in exponential form is:

21805 = 5¹ × 7² × 89¹

Step-2: Prime Factorization of 21818

Prime factors of 21818 are 2, 10909. Prime factorization of 21818 in exponential form is:

21818 = 2¹ × 10909¹

Step-3: Factors of 21805

List of positive integer factors of 21805 that divides 21805 without a remainder.

1, 5, 7, 35, 49, 89, 245, 445, 623, 3115, 4361

Step-4: Factors of 21818

List of positive integer factors of 21818 that divides 21805 without a remainder.

1, 2, 10909

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21805 and 21818. The biggest common factor number is the GCF number.
So the greatest common factor 21805 and 21818 is 1.

Also check out the Least Common Multiple of 21805 and 21818