Every positive [[Integer]] greater than $1$ is either [[Prime Number|Prime]] or can be written *uniquely* (up to order) as the product of [[Prime Number|Primes]], *eg.* every positive [[Integer]] can be uniquely [[Factor|Factorized]]. >[!tip] [[Theorem]] >If $n$ is a [[Composite Number|Composite]] [[Integer]], then $n$ has a [[Prime Number|Prime]] divisor $\le \sqrt{n}$. >[!example]- >$ 48 = 2^4 \cdot 3 $