https://marco.org/2007/11/14/paul-holy-crap-the-32-bit-unsigned-integer
Paul: “Holy crap!!”
The 32-bit unsigned integer limit is 4,294,967,295 - only 3,451 more than that. My guess is it’s a bug that set the value to negative 3,451, and it wrapped around via negative overflow in the unsigned value.
Either that, or your site’s been crashing a lot.