how do i divide (reduce) this period in half or three quarters?

0000000000000000000000000000000000000000000000000000000001000000:
000000000000000000000000000000000000001ffffffffffffffffff


I would like to try to solve the puzzle but i have to reduce it. I would also avoid starting from the first number, I believe many have already tried it from the beginning.

Thank you very much