page two The prime factors of  162  are  2 x 3 x 3 x 3 x 3. Did you get it? Even more interesting is the fact that this is the only way to get 162 using prime numbers! The answer can also be written this way:  162 = 2 x 3 x 3 x 3 x 3  =  2 x 34  using exponents. This makes it quicker to write, especially if there are a lot of factors. Here's another example: 288 = 2 x 2 x 2 x 2 x 2 x 3 x 3 = 25 x 32 Sometimes you'll see powers written using this symbol: ^ when the displaying device can't show an exponent properly. This often happens on calculators. For example: 150 = 2 x 3 x 5 x 5 = 2 x 3 x 52 = 2 x 3 x 5^2 Here's another one, backwards, just to make sure you've got it: 2^3 x 3 x 4^2 = 23 x 3 x 42 = 2 x 2 x 2 x 3 x 4 x 4 = 384 Every composite number can be written just one way as the product of prime numbers. You try some. We have a special calculator that will check any number that you enter, and tell you if it's prime. If it isn't, it will give you the prime factors that multiply together to make the number. Give it a try. You can enter any number up to eighteen digits long, and it will tell you the prime factors. CALCULATOR Note that if a number is prime, the calculator just gives you the number back. Try 17. It will say just 17, because 17 is prime. (not 17 x 1, because 1 is not a prime number) So how do you find prime factors yourself, without a calculator? Go to page three and we'll show you!

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