A self referential sequence

The sequence $G=\{1,2,2,3,3,4,4,4,5,5,5,\dots \}$ is defined by:
$G_n=$number of occurences of $n$ in the sequence.

$G_4=3\Rightarrow$the number $4$ occurs $3$ times in the sequence.

What is $m=G_{123456789101112}$?

Find the smallest $n$ such as $G_n=123456654321$

You are given $1684,128276792$ for $123456,123321$

Answer format: $m,n$

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