what is composite number
A composite number is a positive integer that has a factor other than 1 and itself. For instance, 6 is a composite number because: 1  it is positive. 2  it has a factor other than 1 and itself (both 2 and 3 are factors of 6).
Composite Number. A composite number is a positive integer which is not prime (i.e., which has factors other than 1 and itself). The first few composite numbers (sometimes called composites for short) are 4, 6, 8, 9, 10, 12, 14, 15, 16, ... (OEIS A002808), whose prime decompositions are summarized in the following table. Note that the number 1 is a special case which is considered to be neither composite nor prime.