12. There is a class of five-digit numbers, where the difference (larger number minus smaller number) between any two digits is no less than 2. There are $\qquad$ such five-digit numbers.
【Analysis】
Starting from the smallest of the 5 numbers, we find that the smallest number can only be 0 or 1: If the smallest number is 0, then the 5 numbers can be one of the following five possibilities: $0,2,4,6,8,0,2,4,6,9,0,2,4,7,9,0,2,5,7,9,0,3,5,7,9$. For each possibility, there are $4 \times 4 \times 3 \times 2 \times 1=96$ five-digit numbers that can be formed; If the smallest number is 1, then the 5 numbers can only be $1,3,5,7,9$, which can form $5 \times 4 \times 3 \times 2 \times 1=120$ five-digit numbers; Therefore, there are a total of $96 \times 5+120=600$ such five-digit numbers.