The answer is a 9-digit number.
To find it, get a calculator and press these keys:
12×11×10×9×8×7×6×5×4×3×2×1
then record the number you see on your calculator in the answer box
If you use a cheap calculator that only handles up to 8-digit numbers,
that will be too big a number for it to handle and you'll get an error
message. In that case leave out 10, that is, press
12×11×9×8×7×6×5×4×3×2×1
which won't be too big and then stick a 0 on the end of the result.
Edwin
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