**Prime numbers**. We are so used to them in Mathematics right?

And we usually end up wondering why are we studying about these numbers and formulae and whether there is any use to these in our real life.

Well, if you consider prime numbers, yes there are some really cool uses.

Whether you know or don’t know what Prime numbers are, let me very briefly explain what are those now.

A Prime Number is a number that is only divisible by itself and by 1.

For example, the numbers 2,3,5,7,11 are Prime Numbers.

Prime numbers are natural numbers (whole numbers) and they are greater than 1.

The list of Prime numbers between 1 and 100 is quite popular.

But from the definition we might think that as numbers get larger, there won’t be Prime numbers left.

However this notion is wrong as we have an infinite number of Prime numbers.

Just that they will occur less frequently in the number series as the numbers get bigger.

So throughout our number series starting from 1 and going on infinitely, we have infinite Prime Numbers sprinkled in the series.

And, interestingly, all of the numbers in the series can be produced simply by using Prime Numbers.

For instance, 20 can be written as 5x2x2. 100 can be written as 5x5x2x2 and so on.

In this context Prime Numbers can be referred to as basic level numbers.

It is because, we can pick any number and write it in terms of factors of other numbers. When no more factoring can be done, we are left with Primes.

Also in this sense, Primes can be called the building blocks too!

This property of factorization is what makes Prime numbers interesting and hence useful.

So we can multiply a heap of Prime numbers to find a really large Prime number.

However, when you are given with a very large number, factoring it back into Prime numbers is not easy peasy.

For instance, it is easy to factorize 30 as 3x3x5. But when you are given a 7 or 8 digit number, it is not that easy to factor back that number into Primes.

And imagine how really hard it will be to factorize a 100 or 200 digit number!

Here’s where Primer numbers are put to good use in encryption technology.

## Computer encryption technology

You can pick two really large Prime numbers and multiply them to get a super large Prime number.

However, if you are given a super large Prime number, finding out which two Prime numbers went together to make that super large Prime number is impossible.

Theoretically, it is not impossible. But it would take a lot of time, the amount of time we don’t have, to find those Prime numbers.

So in **computer encryption** Prime numbers are used.

That means whenever you make a purchase online using your credit card, or login to your bank or use encrypted messenger or email feature, you are making use of Prime numbers.

And the use of Prime numbers don’t stop there.

## Prime numbers in Engineering and machinery

In the design of **turbomachinery and gas turbines**, for balancing reasons and for high efficiency, the number of stators N is set to be a Prime number.

## Encryption

The **Enigma machine**, an encryption machine used by the Germans during the Second World War, used Primes for strong encryption.

## Prime numbers and aliens!

The search for **extraterrestrial intelligence** brings us to Prime numbers too. If we ever happen to communicate with super intelligent aliens, we would be using Primes to send out our message.

Similarly, if we happen to receive a sequence of noise or a signal that’s different from a “normal” signal in space, and if that signal that can be decrypted using Primes, then it is most likely that a super intelligent alien species exists at that space.

## Prime numbers in the biological world

Even in the biological world we have Prime numbers being used. Cicadas, a kind of bugs hibernate for years – mostly 13 or 17 years before they come out to breed.

And they die, their eggs hatch and we get to see the next generation in 13 or 17 years.

By spacing their outward appearance in Primed years, **Cicadas** make it least likely for any predator to jeopardize their existence.

Many potential predators have 2-5 year of life cycle and hence that’s how Cicadas carry on genetically.

Those are some interesting uses of Prime numbers right?

If you have been taking Prime numbers for granted, I hope now you will take them a lot more seriously.

Please share this video with your friends so they too can know this!