The prime factorizations of 54 and 72 are shown below. prime factorization of 54: 2, 3, 3, 3 prime factorization of 72: 2, 2, 2, 3, 3 using the prime factorizations, what is the greatest common factor of 54 and 72? 2 x 3 2 x 3 ´x3 2 x2 x3 x 3 2 x2 x2x3 x 3 x 3 p. s those x stands for multiplying