# Problem of the Week Problem C These Primes are Squares!

The number $$7$$ has only two positive factors, $$1$$ and itself. A positive integer greater than $$1$$ whose only positive factors are $$1$$ and itself is said to be prime.

A perfect square is an integer created by multiplying an integer by itself. The number $$25$$ is a perfect square since it is $$5 \times 5$$ or $$5^2$$.

Determine the smallest perfect square that has three different prime numbers as factors.

Extension: Determine all perfect squares less than $$10\,000$$ that have three different prime numbers as factors.