Prime Division (dr.hackenstein, Crabman, Hypnotic Owl)

Prime Division is a fun game about prime factorization. Divide increasingly high numbers down to 1 by tapping on their prime factors. You have 10 seconds for each number. Divide in descending order of the primes to get the most points and earn experience. Every five correct divisions you reach the next stage. Stages increase in difficulty and introduce new prime numbers. However, the first mistake ends the game and sets you back to stage 0. Every stage you reach grants you experience as well. Gain enough experience to level up and unlock additional game modes.

The game was made for Android and thus a couple of features like online highscores don't work. A free version with all features can be downloaded on Google Play Store.