C Programming - Is that a Prime Number?

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The problem is to find out whether a number is prime or not?

This is the one best solution that I could find out!!!
Solution:

/* returns 1, if number is prime else 0 */
int prime(int number)
{
    int iter,bound;
    if (!(number % 2)) return (number == 2);
    if (!(number % 3)) return (number == 3);
    if (!(number % 5)) return (number == 5);
    for(iter = 7; (iter * iter)<= number; iter += 2)
        if ( number % iter == 0 )
            return 0;
    return 1;
}

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