In a response to a similar question, Dr. Pete from our friends at the Math Forum said:
>From: Doctor Pete Subject: Re: Is Zero Even, Odd, or Neither?
Zero is an even number. An integer n is called *even* if there exists an integer m such that n = 2m, and *odd* if n+1 is even. From this, it is clear that 0 = (2)(0) is even. The reason for this definition is so that we have the property that every integer is either even or odd.<
So since by definition, every integer (An integer is a number with no fractional part.) must be either even or odd. Zero, while it may be very special, is an even number.