Explanation:
In number theory, the prime factors of a positive integer are the prime
numbers that divide that integer exactly, without leaving a
remainder. The process of finding these numbers is called integer factorization, or prime factorization. A prime factor can be visualized
by understanding Euclid's geometric position. He saw a whole number as a line
segment, which has a smallest line segment greater than 1 that can divide
equally into it.
For a prime factor p of n,
the multiplicity of p is the largest exponent a for which pa divides n. The prime
factorization of a positive integer is a list of the integer's prime
factors, together with their multiplicity. The fundamental theorem of
arithmetic says that every positive integer has a unique prime factorization.
In number theory, integer factorization or prime factorization is the breaking down of
a composite number into smaller non-trivial divisors, which when
multiplied together equal the original integer. (Our solved example in
mathguru.com uses this concept).
To shorten prime factorization, numbers are often expressed in
powers, so

http://en.wikipedia.org/wiki/Prime_factor
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