Find the pattern between the numbers

Given:
2 rows of numbers
x ---> y
352921050910885 617040243
352921051251529 617612100
353887050135683 716342643
354897052756906 619157327
356966055365839 ???
The number "x" goes through an unknown algorithm and we get the number "y".
Task: find the pattern, i.e. the algorithm by which the number "x" is "run" to obtain the number "y" (if that is possible at all).
Details:
- at the moment 4 pairs of numbers x->y are known. There is a fifth one, but it is kept to check your algorithm
- "x" is a 15-digit number, "y" is a 9-digit number
- the payment stated is the minimum, I will listen to your proposals