This app can tell you if a number between 0 and 20000 is prime or not.
It can also determine all divisors of any number less than 10000000.
Fancy a game? Then you can try the quiz and collect points.
Siri Shortcuts are also supported:
You can also use your shortcuts to check whether your number is a prime number or not.
Another shortcut can give you all the prime numbers from 0 to your entered number in a list.
A shortcut can be used to determine all divisors of any number less than 100000, so the shortcut doesnt take too long.