How to read in really big integers

I am trying to read in a file such as http://paste.ubuntu.com/p/pxmwPXkNNk/.The list of integers should go into an array. I have learned (How to read in a list of integers into an array - #10 by lesshaste) that

using JSON
numbers = JSON.parsefile("input.txt")

works very nicely… except it completely falls over with the large integers. In this particular case it just replaces them with 0s.

How can I read in this list of integers as BigInts?

No need to open a new thread. The discussion can continue in How to read in a list of integers into an array - #14 by kristoffer.carlsson.