Prove it Too 2!

Let $$S(n)$$ be the set of the digits of $$n$$. Find the smallest natural number $$n$$ such that $$S(n^2)$$ is a proper subset of $$S(n)$$.

Clarification:
A set $$A$$ is a proper subset of another set $$B$$ if all elements of $$A$$ is in $$B$$, but $$A \neq B$$.

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