The number 1 is neither prime nor composite. To understand why, let’s define what prime and composite numbers are.
A prime number is defined as a natural number greater than 1 that has no positive divisors other than 1 and itself. In simpler terms, it can only be divided evenly (without leaving a remainder) by 1 and the number itself. Examples of prime numbers include 2, 3, 5, 7, etc.
A composite number, on the other hand, is a natural number greater than 1 that has more than two positive divisors. This means composite numbers can be divided evenly by numbers other than 1 and themselves. Examples of composite numbers are 4 (divisible by 1, 2, and 4), 6 (divisible by 1, 2, 3, and 6), and so forth.
Now, since 1 does not meet the criteria for either category—it is not greater than 1—it cannot be classified as prime or composite. This is a unique property of the number 1, and it is essential in number theory.