What is the Least Common Multiple of 623 and 640?

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 623 and 640 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 623 and 640, than apply into the LCM equation.

GCF(623,640) = 1
LCM(623,640) = ( 623 × 640) / 1
LCM(623,640) = 398720 / 1
LCM(623,640) = 398720

Least Common Multiple (LCM) of 623 and 640 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 623 and 640. First we will calculate the prime factors of 623 and 640.

Prime Factorization of 623

Prime Factorization of 640

Now multiplying the highest exponent prime factors to calculate the LCM of 623 and 640.

LCM(623,640) = 7¹ × 89¹ × 2⁷ × 5¹
LCM(623,640) = 398720