What is the Least Common Multiple of 670 and 685?

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 670 and 685 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 670 and 685, than apply into the LCM equation.

GCF(670,685) = 5
LCM(670,685) = ( 670 × 685) / 5
LCM(670,685) = 458950 / 5
LCM(670,685) = 91790

Least Common Multiple (LCM) of 670 and 685 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 670 and 685. First we will calculate the prime factors of 670 and 685.

Prime Factorization of 670

Prime Factorization of 685

Now multiplying the highest exponent prime factors to calculate the LCM of 670 and 685.

LCM(670,685) = 2¹ × 5¹ × 67¹ × 137¹
LCM(670,685) = 91790