The story of prime numbers

Since the revision of the mathematics curriculum for primary school in 2017, prime number becomes a compulsory part of the resultant curriculum for primary students. Most people remember prime numbers as nasty integers such as 19, 37, 53, 71 etc.

A prime number is a natural number greater than 1 that cannot be formed by multiplying two smaller natural numbers together. Therefore, a prime number can only be written as the product of 1 and itself. Those which are not prime numbers can be written as the products of all prime numbers and are called composite numbers. Take for example, 5 can only be written as 1×5 and is a prime number. 8 can be written as 2x2x2 and is NOT a prime number.

Prime number has been a subject of many study by mathematicians since thousands of years ago. Still, there are open questions concerning prime number which remain unsolved even today. Because of its unusual properties, prime number is widely used in public-key cryptography (the science of encrypting and decrypting information as often seen in spy movies) today.