Graduate Management Admission Test (GMAT) Practice Test

What is the only even prime number?

1. 2

2. 4

3. 6

4. 8

The correct answer is: 2

The only even prime number is 2. A prime number is defined as a number greater than 1 that has no positive divisors other than 1 and itself. For 2, the only divisors are indeed 1 and 2, satisfying the definition of a prime number. When it comes to even numbers, they are all divisible by 2, which means they have at least three divisors: 1, 2, and the number itself. This property disqualifies them from being prime, as a prime number cannot have more than two distinct positive divisors. Looking at the other choices: 4 is divisible by 1, 2, and 4; 6 is divisible by 1, 2, 3, and 6; and 8 is divisible by 1, 2, 4, and 8. Each of these numbers has more than two divisors, making them composite and therefore not prime. 2 stands apart as the only even number that fulfills the criteria of a prime number.