Links
• Prime Numbers Home Page
• Interesting Facts about Prime Numbers
• Uses of Prime Numbers
• Theories about Prime Numbers
• Prime Number Theorem
• Twin Primes
• Sieve of Eratosthenes
• Ulam Spirals
Calculators
• 1. Find all Primes in a range
• 2. Find the Next Prime Number
• 3. Factor a Number
• 4. Find twin Primes
• 5. Create your own Ulam Spiral

Introduction

I am fascinated by prime numbers. I remember as a child trying to understand the subtle difference between odd numbers and prime numbers. Although I am no mathematician I still retain an interest in prime numbers today. I was reading a text book on the history of mathematics when I realised (the book told me actually) that there is no formula to predict prime numbers and that this fact is used as a basis for modern SSL encryption over the internet and has a range of uses as well.

As an adult I have dreamed of finding a formula to predict prime numbers, but having read about what some very smart people have already tried, I have to admit defeat. There are much better mathematical minds than mine out there with super computers looking for formula to predict prime numbers.

Definition

A prime number is a number that has exactly two distinct divisors, 1 and itself. The number 1 is by definition not prime. The first prime number is 2.