Answer:
15 is a composite number.
What are all composite number?
In basic Mathematics, the numbers that have more than two factors are known as composite numbers. For example, factors of 6 are 1, 2, 3 and 6. Thus, there are four factors in total, and 6 is a composite number. The first ten composite numbers are 4, 6, 8, 9, 10, 12, 14, 15, 16, 18. To understand better, have a look at the following examples.
Therefore, your answer is 15