Prime Numbers
2357111317192329313741434753596167717379838997
A prime number has exactly two factors: 1 and itself. For example, 7 can only be divided evenly by 1 and 7.
Prime and Composite Numbers Ocean Game
Dive into a sparkling ocean and put your number skills to the test! Each game challenges you to catch either prime or composite numbers. A prime-numbered fish and a composite-numbered fish jump from the waves together. Tap the correct fish before it dives back into the sea — and keep up as the fish jump faster!
Grade 4Prime & Composite3 LevelsNumbers 2–99Tap the Fish
Catch the right fish!
One fish shows a prime number, and the other shows a composite number. Follow the instruction above the ocean and tap the matching fish before it dives underwater. Miss the correct fish and the game ends. How many can you catch?
Choose Your Level
Choose a number range. Each new game randomly chooses Prime or Composite.
QUICK GUIDE
Prime and Composite Numbers
A factor is a whole number that divides another number evenly, with no remainder. Numbers greater than 1 are either prime or composite — it depends on how many factors they have.
Composite Numbers
468912
A composite number has more than two factors. For example, 12 has factors 1, 2, 3, 4, 6 and 12.
Every whole number from 2 to 99 that is not prime is composite.
Remember: 0 and 1 are neither prime nor composite, so they do not appear in this game. 2 is the only even prime number! Every other even number greater than 2 is composite. For example, 23 is prime, but 24 is composite.
See the Fish Jump!
Watch a prime-numbered fish and a composite-numbered fish leap out of the waves, one after the other.
How to play: Each game asks you to catch either PRIME or COMPOSITE numbers. Two fish jump at a time. Tap the fish with the correct number before it dives back into the ocean! The fish get faster after every catch. Miss the correct fish and it's Game Over!