Least Common Multiple  of 16 and 21 is 336

How to find the Least Common Multiple of 16 and 21?

On this page below, we'll use the Prime Factorisation, and the List of Multiples method to find out the LCM of 16 and 21.

Follow the steps below, and let's calculate the LCM of 16 and 21.


Method 1 - Prime factorization

Step 1: Create a list of all the prime factors of the numbers 16 and 21:

Prime factors of 16

The prime factors of 16 are 2, 2, 2 and 2. Prime factorization of 16 in exponential form is:

16 = 24

Prime factors of 21

The prime factors of 21 are 3 and 7. Prime factorization of 21 in exponential form is:

21 = 31x71


Step 2: Identify the highest power of each prime number from the above boxes:

24, 31, 71


Step 3: Multiply these values together:

24x31x71=336


Step 4: The result:

As seen on the calculation above, we have now obtained the LCM of 16 and 21.

The Least Common Multiple of 16 and 21 is 336.


Method 2 - List of Multiples

Find and list multiples of each number until the first common multiple is found. This is the lowest common multiple.


Multiples of 16:

16, 32, 48, 64, 80, 96, 112, 128, 144, 160, 176, 192, 208, 224, 240, 256, 272, 288, 304, 320, 336, 352, 368, 384

Multiples of 21:

21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, 252, 273, 294, 315, 336, 357, 378, 399


Therefore,

LCM(16, 21) = 336