What is the smallest natural number that has exactly 6 factors?

Explanation

1. 01

   A number with 6 factors has the form $p^5$ or $p^2 \times q$ (since $6 = 6 \times 1 = 3 \times 2$).

2. 02

   Smallest $p^5$ is $2^5 = 32$. Smallest $p^2 \times q$ is $2^2 \times 3 = 12$.

3. 03

   So the answer is 12 (factors 1, 2, 3, 4, 6, 12).