private void computePrimeFactors() {
        long X = N;
        long i;
        for (i = 2; i != 1 && i * i < X; i++) {
            if (X % i == 0) {
                primes[primeCount++] = i;
                do {
                    X /= i;
                } while (X % i == 0);
            }
        }
        if (X != 1) primes[primeCount++] = X;
        for (long pri : primes) {
			System.out.print(pri + "-");
		}
        System.out.println();
    }