What is the Least Common Multiple of 39420 and 39440?

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 39420 and 39440 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 39420 and 39440, than apply into the LCM equation.

GCF(39420,39440) = 20
LCM(39420,39440) = ( 39420 × 39440) / 20
LCM(39420,39440) = 1554724800 / 20
LCM(39420,39440) = 77736240

Least Common Multiple (LCM) of 39420 and 39440 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 39420 and 39440. First we will calculate the prime factors of 39420 and 39440.

Prime Factorization of 39420

Prime Factorization of 39440

Now multiplying the highest exponent prime factors to calculate the LCM of 39420 and 39440.

LCM(39420,39440) = 2⁴ × 3³ × 5¹ × 73¹ × 17¹ × 29¹
LCM(39420,39440) = 77736240