What is the Least Common Multiple of 39840 and 39860?

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 39840 and 39860 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 39840 and 39860, than apply into the LCM equation.

GCF(39840,39860) = 20
LCM(39840,39860) = ( 39840 × 39860) / 20
LCM(39840,39860) = 1588022400 / 20
LCM(39840,39860) = 79401120

Least Common Multiple (LCM) of 39840 and 39860 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 39840 and 39860. First we will calculate the prime factors of 39840 and 39860.

Prime Factorization of 39840

Prime Factorization of 39860

Now multiplying the highest exponent prime factors to calculate the LCM of 39840 and 39860.

LCM(39840,39860) = 2⁵ × 3¹ × 5¹ × 83¹ × 1993¹
LCM(39840,39860) = 79401120