What is the Least Common Multiple of 21216 and 21220?

Least common multiple or lowest common denominator (lcd) can be calculated in two way; with the LCM formula calculation of greatest common factor (GCF), or multiplying the prime factors with the highest exponent factor.

Least Common Multiple of 21216 and 21220 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 21216 and 21220, than apply into the LCM equation.

GCF(21216,21220) = 4
LCM(21216,21220) = ( 21216 × 21220) / 4
LCM(21216,21220) = 450203520 / 4
LCM(21216,21220) = 112550880

Least Common Multiple (LCM) of 21216 and 21220 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 21216 and 21220. First we will calculate the prime factors of 21216 and 21220.

Prime Factorization of 21216

Prime Factorization of 21220

Now multiplying the highest exponent prime factors to calculate the LCM of 21216 and 21220.

LCM(21216,21220) = 2⁵ × 3¹ × 13¹ × 17¹ × 5¹ × 1061¹
LCM(21216,21220) = 112550880