$\large { {2017 \, 2003 \, 2001 \ldots 7 \, 5 \, 3 \, 2} }$

The above expression shows the concatenation of the prime numbers less than or equal to 2017 written backwards.

Let $L$ and $S$ denote the number of digits and the sum of digits, respectively, of this large number. What can you say about the number obtained from the expression given below? $\dfrac1{10} \left[ (S-L) \pmod{2016} \right]$

It is a perfect cube
It is a prime number
It is a number less than 100
It is a perfect square

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I used a primes under n generator to find all primes under 2017, added them to an empty string, and found l and s.