Fundamental theorem of arithmetic states that every integer larger than 1 is either a Prime number or unique product of Prime numbers. Well-known truth included in the book of "Elements" by Euclid dated back to 300 BC.
It is also believed that every even number larger than 2 is the sum of two Prime numbers, which is known as the Goldbach riddle.
Our simple Microbit code for kids introducing Prime numbers, so to speak building blocks of our number system, is below.
Press A and it picks a random number. When shaked, it shows if it is prime.