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how do you find this to be a prime number or not..... 222221 
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how do you find this to be a prime number or not..... 222221
by marty.frmn on Thu Oct 22, 2009 7:17 am
how do you find this to be a prime number or not..... 222221????
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by stapel_eliz on Thu Oct 22, 2009 1:33 pm
Divide by primes. If something no larger than the square root of the number "fits", it's composite. Otherwise, it's prime. 
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