Why you should care about Prime Numbers

"We've got Amazon Prime!"...

is the reaction some kids have when they hear me bring this up outside of a maths classroom.

But this isn’t about free shipping or streaming your favourite movies. This is about the numbers protecting you every time you buy something online—like that Christmas gift for your kid.

Stick with me here.

For a lot of kids (and let’s be honest, a lot of adults too), the big question is:

“When am I ever going to use prime numbers in real life?”

Great question. Here's your answer:

Prime numbers are the silent guardians of the internet.

They are the internet's bodyguards.

Every time you use 'tap and go' or shop online, prime numbers are in action scrambling your payment details into secure, indecipherable codes.

Why primes? Because breaking down a huge number into its original prime factors is one of the hardest problems in mathematics. It's so hard, there's a $1 million prize for anyone who can crack it. (Spoiler: even supercomputers are stumped.)

Let's break it down:

All whole numbers can be written as a multiplication of primes.

Take the number 449,623. It can be written as the primes 521 x 863. Easy enough.

Now imagine numbers hundreds of digits long. These monsters are scrambled into a code using prime numbers. A magic called encryption. Without knowing the specific prime factors used to create the encryption keys, breaking these codes is practically impossible.

It’s the reason online shopping, banking, and social media don’t turn into a hacker's playground. You don’t need to be a computer whiz to get why they matter.

Now maths isn’t a spectator sport here. Maths isn’t just for tests. It’s about building real-world problem-solving skills.

If you want your kids to understand the systems that run our world, get involved!

Prime numbers might seem abstract, but they’re the key to our digital future.

In school, prime numbers often show up in lessons on Highest Common Factor and Lowest Common Multiple. But here’s the problem: kids know what they are but rarely understand why they matter. Without answering the “Why do I need to know this stuff?” question, it’s no surprise they struggle to apply primes in real-world contexts.

Click here for an example that make these abstract concepts relevant to the real world.

Learning maths can sometimes feel like 99% frustration, 1% inspiration.

It's okay to get frustrated, it’s okay to feel like a toddler learning to walk and continually falling flat on your face. It’s part of the process.

But when that “Oh, I get it!” moment hits, it’s like flipping on the light switch.

The light goes on and you see everything and suddenly see how the world fits together.

If you doze through the basics—the prime numbers, the fractions, the algebra—you’re skipping the fundamental tools we use to create the innovation we all rely on.

Next time you hear about a data hack on the news, think about the prime number systems that could’ve stopped it.

Stay curious,

Nici

P.S.

If this email sparked your curiosity, share it with someone who’d enjoy learning why prime numbers matter.

Or better yet, forward it to a teacher, a parent, or a budding mathematician.

The more people who see the power of primes, the better!