What is the smallest prime number?

The smallest prime number is 2. A prime number is defined as a natural number greater than 1 that has no positive divisors other than 1 and itself. In the case of 2, it is only divisible by 1 and 2, meeting the criteria for primality.

Furthermore, it is the only even prime number; all other even numbers can be divided by 2, making them composite rather than prime. As for the other options, 0 and 1 do not qualify as prime numbers. Zero is not a natural number, and one only has one positive divisor, which is itself, thus it is not classified as prime either. The number 3 qualifies as a prime number, but it is larger than 2, making 2 the smallest. Therefore, 2 is undeniably the smallest prime number.