why is zero even?
Because it shares all the properties that characterize even numbers.
Parity of zero
zero shares all the properties that characterize even numbers
what is parity of zero? It is the quality of an integer (zero) being even or odd. Zero has the parity of even.
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Parity of zero [SEP] Introduction
Zero is an even number. In other words, its parity—the quality of an integer being even or odd—is even. This can be easily verified based on the definition of "even": it is an integer multiple of 2, specifically . As a result, zero shares all the properties that characterize even numbers: for example, 0 is neighbored on both sides by odd numbers, any decimal integer has the same parity as its last digit—so, since 10 is even 0 will be even, and if is even then has the same parity as —and and always have the same parity. Zero also fits into the patterns formed by other even numbers.