Explanation:
What other numbers are of this form have exactly four factors?
8 = 2³ has 4 factors 1, 2, 2², 2³
For any prime p, p³ has 4 factors 1, p, p², p³
Do all the perfect cubes have exactly four factors?
If p is not prime, then it is not true anymor
For instance, 8³ has more than 4 factors 1, 2², 2³,:
Is it true that all numbers that have exactly four factors are perfect cubes?
6 has 4 factors : 1, 2, 3, 6 but this is not a perfect cube.