We know that additive identity of any whole number is 0. So, additive identity of 498 is 0.
i.e. 0 + 498 = 498.

We have, 5437 x 1001 = 5437 x (1000 + 1)
                                 = 5437 x 1000 + 5437 x 1 [by distributive property of multiplication over addition]
                                = 5437000 + 5437 = 5442437.

390.

We have, 285 x 5 x 60 = (5 x 60) x 285
                                 = 300 x 285 = 85500.

2193, 2191.

The successor of given numbers are as follows:

For 3 + 6, start from 3 and make 6 jumps to the right by unit distance each. Then, we reach at 9.
          
So,  3 + 6 = 9.

(a) 361
(b) 441.

According to the patterns of whole number,

Yes, if the product of two whole numbers is zero, then one or both of them will be zero. Since, we know that the product of any whole number with zero is always zero i.e. a x 0 = 0, where a is any whole number and 0 x 0 = 0. Some examples are as follows:

Let an odd natural number other than 1 be 3.
Predecessor of 3 = 3 - 1 = 2
Successor of 3 = 3 + 1 = 4
\(\therefore\) Product = 2 x 4 = 8
Now, LCM of predecessor and successor = 2 x 2 = 4
\(\therefore\) The greatest number which always divides the product of predecessor and successor of an odd natural number other than 1 is 4.

Here, we have
(a) 0 x 0 = 0
(b) \(\frac{0}{2}=0\)
(c) \(\frac{8-8}{2}=\frac{0}{2}=0\)
(d) 2 + 0 = 2
Hence, 2 + 0 = 2 is not zero.

1 million = 1000000
So, successor of 1000000 = 1000000 + 1
 = 1000001.

We have, 1 lakh = 100000
\(\therefore\) Predecessor of 100000 = 100000 - 1 = 99999.

If a and b are any two whole numbers, then a + b = b + a. This is commutative property.

The product of non-zero whole number and its successor is always an even number.

Here, we will find successor of 300, 300 + 1 = 301
So, 300 is the predecessor of 301.

(i) 17136
(ii) 75708.