IMC Key Stage 2 · 4. Primes, divisors and perfect squares
Factorise into primes first; the exponents then tell you the number of divisors, whether a number is a square, and how many zeros a product ends with.
IMC Key Stage 2 (EMIC) – Selected topics
Recognise primes and test whether a number is prime.
Write a number as a product of primes and count its divisors.
Use even exponents to recognise and build perfect squares and cubes.
Count zeros at the end of a long product by counting factors 5.
Test cases in order and trap a number between two squares.