In infinitely many ways. However, if you want powers of positive integers only, then you can express 64 as a power of 2, 4, 8 and of 64 itself.
Exponents are used to replace repeated factors. Prime numbers won't use exponents because they don't have repeated factors. To express the prime factorization of a particular composite number using exponents, just count. 2 x 2 x 2 x 3 x 3 = 72 23 x 32 = 72
5^2
The prime factorization of 25 using exponents is 52
Numbers expressed using exponents are called powers. When writing a number expressed as an exponent, the number is called the base.
Because the expressions are undefined for base = 0.
The base.
321 = 3*107
96 = 25 x 31
60 = 22*3*5
19 is a prime number in its own right and needs no exponents
11 is a prime number in its own right and needs no exponents
22 x 3 x 7