GCF and LCM of 6 and 27

The GCF of 6 and 27 is 3. The LCM of 6 and 27 is 54.

Method 1: list the factors (GCF)

Factors of 6: 1, 2, 3, 6.
Factors of 27: 1, 3, 9, 27.
Common factors: 1 and 3. The greatest of these is 3.

Method 2: prime factorization

6 = 2 × 3
27 = 3 × 3 × 3

GCF: multiply the prime factors both numbers share: 3 = 3.

LCM: multiply every prime the maximum number of times it appears in either number: 2 × 3 × 3 × 3 = 54.

Method 3: Euclidean algorithm (GCF)

Divide the larger number by the smaller and repeat with the remainder until it is 0. The last non-zero remainder is the GCF.

  1. 27 = 4 × 6 + 3
  2. 6 = 2 × 3 + 0

The last non-zero remainder is 3, so GCF(6, 27) = 3.

LCM by listing multiples

Multiples of 6: 6, 12, 18, 24, 30, 36, 42, 48, 54, ...
Multiples of 27: 27, 54, 81, ...
The first number in both lists is 54.

Check: GCF × LCM = product

3 × 54 = 162 = 6 × 27. This always holds for two numbers, so you can find the LCM as (6 × 27) ÷ 3 = 54.

Simplifying the fraction 6/27

Divide the top and bottom by the GCF 3: 6/27 = 2/9.

GCF and LCM of similar pairs

NumbersGCFLCM
2 and 626
3 and 636
4 and 6212
5 and 6130
6 and 7142
6 and 8224
2 and 27154
3 and 27327
4 and 271108
5 and 271135
7 and 271189
8 and 271216

See also: factors of 6 · factors of 27.

Different numbers? Use the GCF and LCM calculator (any amount of numbers) or browse all GCF and LCM pairs.