I was just getting my hands dirty solving some equations of the form $x=\phi(n)$ where $\phi(n)$ is Euler totient function. I know that $\phi(n)$ is even for $n\geq 3$. However, I am wondering that:
Can all even integers $x$ be expressed as $\phi(n)$ where $n$ is an integer?
I start doing some research, the first even number appears to hove no solution is $14$. According to this page, there is no solution to the equation $14=\phi(n)$ for $n\leq 500$. But does it have a solution for $n>500$?
Moreover, what can you say about the above statement?