To determine if the number KP6428K is divisible by 16, we need to consider the divisibility rule for 16.

Divisibility Rule for 16:
A number is divisible by 16 if the last four digits of the number form a number that is divisible by 16.

Given the number KP6428K, we can see that the last four digits are 6428. We need to check if this four-digit number is divisible by 16.

Finding the maximum value of P × K:
To find the maximum value of P × K, we need to consider the possible values of P and K.

Since P and K are single-digit whole numbers, they can take values from 0 to 9.

We can calculate the values of P × K for each combination of P and K and find the maximum value.

| P | K | P × K |
|---|---|-------|
| 0 | 0 | 0 |
| 0 | 1 | 0 |
| 0 | 2 | 0 |
| 0 | 3 | 0 |
| 0 | 4 | 0 |
| 0 | 5 | 0 |
| 0 | 6 | 0 |
| 0 | 7 | 0 |
| 0 | 8 | 0 |
| 0 | 9 | 0 |
| 1 | 0 | 0 |
| 1 | 1 | 1 |
| 1 | 2 | 2 |
| 1 | 3 | 3 |
| 1 | 4 | 4 |
| 1 | 5 | 5 |
| 1 | 6 | 6 |
| 1 | 7 | 7 |
| 1 | 8 | 8 |
| 1 | 9 | 9 |
| 2 | 0 | 0 |
| 2 | 1 | 2 |
| 2 | 2 | 4 |
| 2 | 3 | 6 |
| 2 | 4 | 8 |
| 2 | 5 | 10 |
| 2 | 6 | 12 |
| 2 | 7 | 14 |
| 2 | 8 | 16 |
| 2 | 9 | 18 |
| 3 | 0 | 0 |
| 3 | 1 | 3 |
| 3 | 2 | 6 |
| 3 | 3 | 9 |
| 3 | 4 | 12 |
| 3 | 5 | 15 |
| 3 | 6 | 18 |
| 3 | 7 | 21 |
| 3 | 8 | 24 |
| 3 | 9 | 27 |
| 4 | 0 | 0 |
| 4 | 1 | 4 |
| 4 | 2 |