dnd 5th – How to make a "god" NPC / enemy?

I start a small campaign in a setting with two sensitive races: humans and gods. Humans are just basic human beings, as usual. The gods, however, are not quite the standard gods of D & D: they are far more powerful than humans, but they remain physical beings (they have a body, die when they are killed, can not to grant divine magic directly, etc.). However, they demand worship and govern people fairly directly.

My question is: how can I establish appropriate statistics for these "gods", so that they are not impossible to fight for a medium-high level party (12 years and older) but not too easy to kill when players inevitably try?

I had planned to use high level computers with high statistics, but this seems inappropriate to me. For reference, the group is currently composed of three level four characters.