What is the Least Common Multiple of 20989 and 21009?

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 20989 and 21009 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 20989 and 21009, than apply into the LCM equation.

GCF(20989,21009) = 1
LCM(20989,21009) = ( 20989 × 21009) / 1
LCM(20989,21009) = 440957901 / 1
LCM(20989,21009) = 440957901

Least Common Multiple (LCM) of 20989 and 21009 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 20989 and 21009. First we will calculate the prime factors of 20989 and 21009.

Prime Factorization of 20989

Prime Factorization of 21009

Now multiplying the highest exponent prime factors to calculate the LCM of 20989 and 21009.

LCM(20989,21009) = 139¹ × 151¹ × 3¹ × 47¹ × 149¹
LCM(20989,21009) = 440957901