I have just been playing with the numbers. I do not know how to do this.
But these are the possible combinations of 6 digits that add up to 23.
0 1 2 3 8 9
0 1 2 4 7 9
0 1 2 5 6 9
0 1 3 4 6 9
0 2 3 4 5 9
0 1 2 5 7 8
0 1 3 4 7 8
0 1 3 5 6 8
0 2 3 4 6 8
1 2 3 4 5 8
1 2 3 4 6 7 (added on)
0 2 3 5 6 7
0 1 4 5 6 7
So that is 12 groups of 6 digits.
Now it canot begin with 0 becasue that would not be a proper number.
The digits add to 23 so none of these will be divisable by 3 or 6 or 9. I am not sure what that means, I am getting in a mess.
So I have a lot LESS than
5*5!*11+6! =6600+720 = 7320 ways
plus another 720 = 8050
352 ways certainly sounds possible
Edit
oh dear, I just realize that 1 2 3 4 6 7 is missing. I wonder how many others are missing. I think not many, hopefully none.