What is the prime factorization of 2x3x5x7

This is already in prime factored form. If you multiply 2, 3, 5, and 7 you get 2*3*5*7 = 6*35 = 210

So if your book asked "what is the prime factorization of 210?" then the answer would be 2*3*5*7

I'm using the asterisk symbol * in place of x because x is often used as a variable in algebra.