04/25/2023
Have you ever wondered why the number 1 isn’t a prime, even though 1 is the product of 1 and itself? It actually used to be considered prime, but mathematicians redefined prime numbers just to exclude it!
Mathematicians wanted to simplify the Fundamental Theorem of Arithmetic, which states that every positive integer greater than 1 can be written as a unique product of primes. The order of the primes doesn’t matter.
For example, 12=2*2*3, so the unique prime factors of 12 are 2, 2, and 3. If 1 were prime, there would be lots of different ways to write 12 as a product of primes: 12=1*2*2*3, 12=1*1*2*2*3, 12=1*1*1*2*2*3, etc. Not so unique anymore!
Watch this video from Numberphile to learn more about 1 and prime numbers:
https://hubs.li/Q01GBsd70