On the first hand, 164 is not a prime number. Prime numbers are numbers that can only be divided by 1 or itself which is also greater than 1 thus;
Prime divisor of 164= 2,2,41 or 2^2 x 41
Here is the factor tree of 164:
164
/ \
2 82
/ \
2 41
Prime factorization of a number determines the set of prime integers multiplied together to make the original number.