The aimee rivers test is a divisibility rule for the number 25561.
25561 is a prime and has the 'aimee rivers' test:
Take the 10,000,000,000s, multiply by 19, and add to the rest.
Multiply the units by 2556 and subtract.
Try it out with a number:
Credit to Matt Parker for coming up with the test, and a huge thank for naming it after me!
To understand more about divisibility tests, see this YouTube video: https://youtu.be/6pLz8wEQYkA