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. The number 2 meets this criterion, as its only divisors are 1 and 2. It is the first number that appears in the sequence of prime numbers.

Additionally, 2 is unique because it is the only even prime number; all other even numbers can be divided by 2, meaning they have at least three divisors: 1, 2, and the number itself. This makes 2 the smallest and the only even member of the prime number set.

In contrast, 1 is not considered prime as the definition requires a prime number to be greater than 1. Both 3 and 4 are larger than 2, with 3 being a prime number and 4 being composite, as it has divisors of 1, 2, and 4. Thus, the identification of 2 as the smallest prime number stands confirmed.