Largest prime factor program takes aaaages - Java

Question

So this is problem 3 from project Euler. For those who don\'t know, I have to find out the largest prime factor of 600851475143. I have the below code:

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Answer 1

try this ..

public class LargestPrimeFactor{
public static int largestPrimeFactor(long number) {
    int i;
    for (i = 2; i <= number; i++) {
        if (number % i == 0) {
            number /= i;
            i--;
        }
    }
    return i;
}

/*  change according to ur requirement. 
public static long getLong(String prompt) {
    System.out.print(prompt + " ");
    long mrlong = input.nextLong();
    input.nextLine();
    return mrlong;
}
 */

public static void main(String[] args) {
    //long num = getLong("What number do you want to analyse? ");
    System.out.println(largestPrimeFactor(600851475143l));
}
}