BigInteger a = new BigInteger("1234567890");
BigInteger b = new BigInteger("9876543210");
System.out.println("a + b = " + a.add(b));
System.out.println("a - b = " + a.subtract(b));
System.out.println("a * b = " + a.multiply(b));
System.out.println("a / b = " + a.divide(b));