code: private static BigInteger getFactorial(int number) {
                  BigInteger factorial = BigInteger.ONE;
                  for (int i = number; i > 1; i--) {
                          factorial = factorial.multiply(new BigInteger(Integer.toString(i)));
                  }
                  return factorial;
          }
docs: Computes the factorial of the given number
  
  @param number jBasic number for factorial computation
  @return The factorial of <code>number</code>