What is the Least Common Multiple of 81720 and 81740?

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 81720 and 81740 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 81720 and 81740, than apply into the LCM equation.

GCF(81720,81740) = 20
LCM(81720,81740) = ( 81720 × 81740) / 20
LCM(81720,81740) = 6679792800 / 20
LCM(81720,81740) = 333989640

Least Common Multiple (LCM) of 81720 and 81740 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 81720 and 81740. First we will calculate the prime factors of 81720 and 81740.

Prime Factorization of 81720

Prime Factorization of 81740

Now multiplying the highest exponent prime factors to calculate the LCM of 81720 and 81740.

LCM(81720,81740) = 2³ × 3² × 5¹ × 227¹ × 61¹ × 67¹
LCM(81720,81740) = 333989640