Is 22 prime or composite??

2 Answers
May 7, 2018

22 is composite.

Explanation:

First, review what "prime" and "composite" mean:

A prime number is number greater than 1 that can't be created by multiplying two smaller, natural numbers.

A composite number is a number greater than 1 that can be created by multiplying two smaller, natural numbers.

Let's factor 22:

1 - 22
2 - 11

Because 22 can be formed by multiplying two smaller, natural numbers, it is composite.

Source:
https://en.wikipedia.org/wiki/Prime_number

May 9, 2018

#22# is composite because it has four factors.

Explanation:

A Prime number has only #2# factors - #1# and itself.

The only even number which is prime is #2#, since #2 = 1 xx 2#
All other even numbers are multiples of #2# and therefore have #2# as a factor.

#22 = 1xx22 " " and 22 = 2xx11#
Therefore we can see it has #4# factors and cannot be prime, it is composite.

Numbers which have more than #2# factors are composite numbers,

#1# is neither prime nor composite since it has only #1# factor.

The prime numbers less than #30# are:

#2,3,5,7,11,13,17,19,23,29#