A

**natural**number (i.e. 1, 2, 3, 4, 5, 6, etc.) is called a prime number (or a prime) if it has exactly two positive**factors**, 1 and the number itself.**Natural**numbers that have more than two positive**factors**are called composite. 1 has only one positive**factor**i.e. no.1 only. Hence 1 is neither prime nor composite.Also, what is the smallest prime number and why?

1 is the

**smallest**natural**number**but it has only 1**factor**that is 1 itself. Therefore, 1 cannot be considered as a**prime number**. Next**number**2 is the**smallest**even**prime number**. as 1×1=1,so it is not**prime no**.Why is the number 1 not a prime number?

Answer

**One**: By definition of**prime**! An integer greater than**one**is called a**prime number**if its only positive divisors (factors) are**one**and itself.What is the lowest 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.