This puzzle was inspired by Rally Round 201 (GC6A5GF) but is actually quite different.
THE CACHE IS NOT AT THE LISTED COORDINATES.
Solve the puzzle. The solution is a big (15-digit) number.
Divide the solution by 4223.
Subtract from 243550651209.
Multiply by your original number.
Finally subtract from 62623837978358514865473575 to get the solution.
Check your solution online: 