I am a "Jain" and I would like to answer you that Jainism is not an atheist religion. Some hindu followers claimed it as "Atheist" because Jainism doesn't believe in any creator god, protector god or destroyer god. For someone's claim, we can't be denoted as Atheist to be very frank. read more
If atheist is taken to mean ‘not believing in the existence of a supreme being or a super natural power (God) as the creator of the universe’, then both Jainism and Buddhism can be said to be atheist religions. read more