Find all positive integers n < 1000 that have exactly five factors.
Any number that can be written as X * X * X * X where is X is a prime number has exactly 5 factors
- 2^4
-3^4
-5^4
-7^4 > 1000...
Your answer would be 3 positive integers. Specifically--2, 3, and 5.
+312 
