@Override
  public String toString()
  {
	if (factor == 0)
	{
	  return Long.toString(base);
	}
	else if (factor > 0)
	{
	  return toDecimalString();
	}
	else
	{
	  // factor negative
	  if (base == 0)
	  {
		return "0";
	  }
	  else
	  {
		return Long.toString(base) + ZEROS[-factor];
	  }
	}
  }