I came across these numbers and found interesting, as if they are characteristic.
So I am writing with a brief explanation about them.
To me they are interesting numbers 🙂
The definition is :A number that is the sum of its own digits each raised to the power of the number of digits.
Well Take number 12
= 1^2 + 2^2
12 not equal to 5
So it is not an Armstrong number
Now, take 153
= 1^3 + 5^3+3^3
So it is an Armstrong number. The to the power of 2 in previous example and 3 in the latter example are the number of digits in the number.
So now to go for a four digit number
I think there are ways to generate these number through different Algorithms.
P.S: This is just a reference post.