What is the Least Common Multiple of 81420 and 81440?

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 81420 and 81440 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 81420 and 81440, than apply into the LCM equation.

GCF(81420,81440) = 20
LCM(81420,81440) = ( 81420 × 81440) / 20
LCM(81420,81440) = 6630844800 / 20
LCM(81420,81440) = 331542240

Least Common Multiple (LCM) of 81420 and 81440 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 81420 and 81440. First we will calculate the prime factors of 81420 and 81440.

Prime Factorization of 81420

Prime Factorization of 81440

Now multiplying the highest exponent prime factors to calculate the LCM of 81420 and 81440.

LCM(81420,81440) = 2⁵ × 3¹ × 5¹ × 23¹ × 59¹ × 509¹
LCM(81420,81440) = 331542240