The numbers are falling! Fortunately, you've got the fundamental theorem of arithmetic on your side!
In Prime Shooter, a math game of prime numbers created by Philip Dorrell, press [P] to destroy prime numbers directly, or press 2, 3, 5, 7, E, T, S, or N to reduce composite numbers by dividing them by prime factors less than 20 (E for 11, T for 13, S for 17, and N for 19). Each number you destroy scores you one point, and the numbers get larger and fall faster as your score goes up.
Tip: When fighting off a 256, shout "two two two two two two two two!" in a high-pitched voice, so that "two!" rhymes with "pew!" It won't help you win, but it's fun to say.