Spawn actor every X Round


I have a wave system that spawns enemies every round and increases.
I am having trouble with something,
I want to spawn a special enemy every 5 rounds, how do I find without manually entering: if round =5 spawn. If round=10 spawn etx…
I have infinite number of rounds it would take too long, how would I set up a system that automatically says every 5 rounds spawn enemy?
Many thanks

If round % 5 = 0 spawn

Cheers mate, I knew it was something easy, but I am very bad in mathematics, which does not help in coding…