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UKMT Pink Kangaroo, 2025

Number theory Difficulty 3.0 AMC 10/12 Find the answer United Kingdom

The integer $N$ is the largest six-digit integer with the product of all its digits equal to 180. What is the sum of the digits of $N$ ?

(A) $16$ (B) $17$ (C) $18$ (D) $20$ (E) $21$

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