# Difference between revisions of "Even integer"

An even integer is any integer which is a multiple of $2.$ The even integers are $\ldots, -4, -2, 0, 2, 4, \ldots$; specifically, note that $0$ is even. Every even integer can be written in the form $2k$ for some unique integer $k$.

The sum and difference of any two integers with the same parity is even. The product of any two even integers is not only even but is also divisible by $4.$ The sum of an even integer and an odd integer is odd.

Since every even integer is divisible by $2,$ $2$ is the only prime even integer.

To find how many even integers are between 1 and $x$. You do $\frac {x}{2}$+1