over 1 year ago - /u/JagexAzanna - Direct link

Originally posted by AHeroicLlama

This number choice is really weird to me too - in fact if you Google it right now you get 3 hits on the entire internet - 1 being that news post and the other being the RS Wiki, which states the number is "2.1 billion times 1 billion plus 2.1 billion (the exact formula is (231 - 1) × 109 + 231 - 1). "

No idea why it was selected but I assume they had their very janky reasons.

I believe it was ( Current max int * 1b + Current max int)