Ten digit number
First saw this as a puzzle from Template:Cartalk link, where it is attributed to Martin Gardner.
Puzzle
Find what is unique about this number: 8,549,176,320.
Help
Hint
This is similar to the next letter puzzle
Answer
It is the only ten digit number which has all ten digits (0-9) in alphabetical order
References
- Car Talk Puzzler - sometimes automotive, sometimes more math/logic based.
- Books by Martin Gardner - perhaps the greatest contributer to mathematical puzzles ever.