So is the encryption key the same as the public key exponent e? The number I'm supposed to use as an encryption key is even, and it seems like it can't be the public key exponent because phi(m)=(p-1)(q-1) is also even.
It sounds like you are given $\displaystyle m$, not $\displaystyle e$. So, you need to find $\displaystyle \varphi(m)$. Then the decryption key would be $\displaystyle e^{-1} \pmod{\varphi(m)}$? I dunno.