## Only Self-Enumerating Number

What is the only self-enumerating number in English?

Four. The number four has four letters, making it self-enumerating. Interestingly, there are no self-enumerating numbers in French.

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4 Comments on "Only Self-Enumerating Number"

Oliver S. Daniel says
November 6, 2018 @ 13:08

I thought that a self enumerating (self descriptive) number is a number which indicates, in numbers, the number of the specific numbers in that particular number.
Like 6210001000 for example.
It contains 6 at position 0, indicating that there are six 0s in 6210001000;
It contains 2 at position 1, indicating that there are two 1s in 6210001000;
It contains 1 at position 2, indicating that there is one 2 in 6210001000;
It contains 0 at position 3, indicating that there is no 3 in 6210001000;
It contains 0 at position 4, indicating that there is no 4 in 6210001000;
It contains 0 at position 5, indicating that there is no 5 in 6210001000;
It contains 1 at position 6, indicating that there is one 6 in 6210001000;
It contains 0 at position 7, indicating that there is no 7 in 6210001000;
It contains 0 at position 8, indicating that there is no 8 in 6210001000;
It contains 0 at position 9, indicating that there is no 9 in 6210001000.
Correct me if I am wrong.

A self-enumerating number has the same quantity of letters as the number. One is not self-enumerating because the quantity 1 is not the same number of letters in the word (3).

2100 does not have two-thousand one hundred letters, thus is not self-enumerating.