A composite number is a positive integer that can be formed by multiplying two smaller positive integers. For example, 4 is a composite number because it can be written as 2 x 2. In contrast, a prime number is a positive integer that has no positive integer factors other than 1 and itself.

207 is not a composite number because it has no positive integer factors other than 1 and itself. Specifically, 207 cannot be written as the product of two smaller positive integers, so it is classified as a prime number.