Which of the following is a prime number?

Which of the following is a prime number?

Detailed Explanation

A prime number is a whole number that can be divided evenly by itself and by 1 but not by any other number. 2 is a prime number because its only factors are 1 and 2. 27 has factors of 1, 3, 9, and 27; 9 has factors of 1, 3, and 9; and 12 has factors of 1, 2, 3, 4, 6, and 12.