RunningNumberProduct.java

public class RunningNumberProduct {

    public static void main(String[] args) {

        final int LOWERBOUND = 1; // if you need to sum the nuber divisible by any number, change this one!!!
        final int UPPERBOUND = 10;

        int product = 1; // any product (multipler) need a value higher than 0 (also also: change the name so its clear-er)
        int number = LOWERBOUND;

        while (number <= UPPERBOUND) {
            product = product * number; //here just insted of makingt the int of product sum the next (or the same), you multiply it (product) to the number that follows.
            ++number;
        }
        System.out.println("The sum of  " + LOWERBOUND + " to " + UPPERBOUND + " is " + product);

    }
}