The Math Forum

Ask Dr. Math - Questions and Answers from our Archives
Associated Topics || Dr. Math Home || Search Dr. Math

Is Zero Prime or Composite?

Date: 10/23/95 at 19:31:44
From: Andrew Cotton
Subject: 7th Grade Math Question


I am fairly new to teaching 7th grade math.  We have been studying 
prime and composite numbers.  I have had little difficulty explaining 
that "2" is a prime number and that "1" is neither prime nor composite.  
Then one bright student asked about the number"0."  I was stumped 
and have not been successful at finding a solution.  So, is "0" prime, 
composite, or neither?


Andy Cotton

Date: 11/5/95 at 15:43:30
From: Doctor Jeremy
Subject: Re: 7th Grade Math Question

It is neither.  It is not prime - lots of other numbers divide into it.
(They all do, except for zero itself).  But it is not composite - the
only way you could get zero by multiplying primes together is if 
one of the primes were zero, which isn't the case.

Often when defining prime and composite numbers, the fact that the
number must be greater than one is part of the definition.

-Doctor Jeremy,  The Geometry Forum

Associated Topics:
Middle School Number Sense/About Numbers
Middle School Prime Numbers

Search the Dr. Math Library:

Find items containing (put spaces between keywords):
Click only once for faster results:

[ Choose "whole words" when searching for a word like age.]

all keywords, in any order at least one, that exact phrase
parts of words whole words

Submit your own question to Dr. Math

[Privacy Policy] [Terms of Use]

Math Forum Home || Math Library || Quick Reference || Math Forum Search

Ask Dr. MathTM
© 1994- The Math Forum at NCTM. All rights reserved.