Question

Prime factors of $640$.

Answer 1

Determine the prime factor of $640$.

A prime number is one that only has two factors: one and the number itself.
Finding which prime numbers multiply to produce the original number is known as "prime factorization."

$\begin{array}{rcl}640& =& 8\times 8\times 10\\ & =& 2\times 2\times 2\times 2\times 2\times 2\times 2\times 5\\ & =& 2^7\times 5\end{array}$

Hence, the prime factor of $640$ are $2$ and $5$.