495 (four hundred [and] ninety-five) is the natural number following 494 and preceding 496.
The Kaprekar's routine algorithm is defined as follows for three-digit numbers: Repeating this process will always reach 495 in a few steps.
Once 495 is reached, the process stops because 954 – 459 = 495.
The number 6174 has the same property for the four-digit numbers, albeit has a much greater percentage of workable numbers.
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