Kaprekar's Constant 6174 — Watch the Magic

Pick any 4‑digit number with at least two different digits. Sort digits descending and ascending, subtract, and repeat. You will land on 6174 in at most 7 steps!

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Enter a number like 3524 or tap Random
 Speed: 0.9s
Tip: Numbers like 1000 will be padded as 1000 (leading zeros matter when sorting).
Ready
0/7

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