Prime factorization makes a number into only prime numbers. A Prime number has only 2 factors which are 1 and itself. Composite numbers are everything else except 1 and 0. 1 and 0 are neither prime, nor composite.
The prime factorizatin of 162 is 2,3,3,3,and3.
primes are 1,2,3,5,7,11,13,17,19,23,29,31,41,43,47,53,59,61,67,71,73,79,83,89,91. all others are composites.
3x3x5
Number of primes = 4 Number of composites = 5 Ratio of primes to composites = 4 : 5
2 X 7
2, 3 and 5 (1 is classified as being neither prime nor composite, as primes have exactly two factors and composites have at least 3.)
2^2×3^3
3 x 13 = 39
Actually both are important. Public encryption is based on the product (and so a composite) of two very large prime numbers.
3 x 72 = 147
62 = 2*31
3 x 5 x 5 = 75