480 = 25*3*5
480 240,2 120,2,2 60,2,2,2 30,2,2,2,2 15,2,2,2,2,2 5,3,2,2,2,2,2
480 /\ 48 10 /\ /\ 8 6 /\ 5 2 /\ 4 2 /\ 3 2 /\ 2 2
25 x 3 x 5 = 480
48x102x24x2x52x2x12x2x52x2x2x2x3x2x5=25x3x5
No. It is a factor. A "factorization" is a complete list of factors that, when multiplied, give the number - in this case 100.
Factorization into its smallest factors.
The prime factors of 480 are 2, 5 and 3: 2^5 * 5 * 3 = 480
2 x 2 x 2 x 2 x 2 x 3 x 5 = 480
12.5% of 480= 12.5% * 480= 0.125 * 480= 60
The factorization of a number is a series of numbers that make that number 
In actual fact, the prime factorization of 42 is not 21 x 2, as 21 is not a prime number. The complete prime factorization of 42 is 2 x 3 x 7.
Yes, prime factorization is not an NP-complete problem. It is in fact in the complexity class NP, but it is not known to be NP-complete.