The 6174 Trap

Sort the digits big to small, subtract small to big, repeat. Every 4-digit number lands on 6174.

Your 4 digits (try your birth year)

Speed

Why?

Sorting forgets the order of the digits. After one step only 54 different numbers are left, and they all funnel into 6174. Tap the map to try any number.

Your turn: Which 4-digit number takes the most steps to fall in?

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From the videos

Every number falls into THIS trap