# What is the LCM of 12 15 and 21?

The smallest possible number which is exactly divisible by the given numbers is called LCM or the least common multiple.

## Answer: LCM of 12, 15, and 21 is 420

## Explanation:

LCM of 12, 15, and 21 is the least number which is exactly divisible by all three numbers.

As there are three numbers, listing all the multiples of each number and then identifying the least among the common multiples is cumbersome. We opt for the common division method as it is easy and less time taking.

### LCM of 12, 15, and 21 by Common Division Method

In this division method, we divide the numbers simultaneously with prime numbers and stop it when we don't have a prime number to divide the given numbers.

LCM of 12, 15 and 21 is 2 × 2 × 3 × 5 × 7 which is equal to 420