6. If the hundreds and units digits of a three-digit number are swapped while the tens digit remains unchanged, the new number is equal to the original number. There are $\qquad$ such numbers, and among them, $\qquad$ are divisible by $\mathbf{4}$.
【Answer】20
【Analysis】Key points: Addition and Multiplication Principle, Divisibility
When the hundreds and units digits are swapped, the number remains unchanged, which means the hundreds digit must equal the units digit. Therefore, there are $9 \times 10 \times 1=90$ such three-digit numbers. Considering that the number must be divisible by 4, the units digit must be even. When the units digit is 2 or 6, the tens digit must be odd, giving 5 choices. When the units digit is 4 or 8, the tens digit must be even, also giving 5 choices. In summary, there are $4 \times 5=20$ numbers that are divisible by 4.