What is the name given to someone who rejects all belief in the existence of deities?

I'm an apathiest. it means I feel the existence or non existence of a deity is irrelevant

Nix, We respect your decision & position in this matter. Have a Groovy Day!

Mitch, How beautifully, eloquently & succinctly stated; we Love it! Another bit of food for thought: Hades is the crossover from "Paganism" to "Christianity" as it is actually mentioned, by name, in "The Bible".

Hunger Knowledge , To the believer wouldn't no Satan be a good thing? Think about it. 😉

Mitch, very well said, and thank you.

Always get agnostic and atheist mixed up!

I know answer by mistake wrong giving

I'm a frying pantheist for sure.

To each their own, indeed. Personally, I am a theist; I believe in the existence of God AND Satan, but more so, the ability to do so without the need for religion; essentially, ‘...did God invent religion, or, did religion invent God?’ Nah, I'm yankin' yer chain, though. What it all really boils down to is that EVERY system of beliefs is structured by some sort of foundation; for some it's religion and/or God (or “Gods” in the case of polytheism), for some it's Satan (or “Hades” in the cases of Greco-Roman mythology), while others, they simply don't believe in anything that they can't see or hear or touch—not to say, that is, that they cannot conceive of or understand the concept of beliefs, or, more specifically, any belief system(s), but only that they don't care to deal with the stress of deciding one way or the other. The remainder of belief structures and designations are structured around those three concepts; the remainder of [religious designations] are just subjugation by individuals as a last ditch effort to create a way to fit in SOMEWHERE, or with issues they have with the belief systems of others. Food for thought…

Believing the non-existence of deities of other nations like Greece & Romans to each their own But deny God is to deny Satan