Self describing numbers!
The number 521001000 is a number that describes itself because the digits represent the number of occurrences of each digit specified. That is, 5 represents the number of zeroes, 2 represents the number of ones, and so on.
Another example of this number would be 3211000 which has 3 zeroes, 2 ones, 1 two, and so on.
What is the smallest number that exhibits this property?