Prime Comic Numbers

...13121110987654321 is prime?\Large ...13121110987654321 \text{ is prime?}

Let us define a comic number as one that is created by concatenating all of the integers from 11 to nn, left to right, in descending order. For example, if we let n=12n=12, then our comic number would be 121110987654321121110987654321. What is the first value of nn such that its corresponding comic number is prime?

I got the name "comic number" from the term Descending Concatenation, or D.C. for short.
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