User blog comment:Legionwrex/I figured out how many Reapers there are!/@comment-1978336-20120802110847/@comment-1978336-20120803152313

There would have to be much more than a million Reapers, even if they aren't S-class. The galaxy is huge. The Milky Way has anywhere from 200 to 400 billion stars, and is roughly 120,000 light-years in diameter. They would need incredibly large numbers in order to effectively carry out their full-scale galactic invasion. Personally, since S-class Reapers appear to be the only Reapers capable of spaceflight, and thus likely serve as a mode of interplanetary transportation for destroyers and infantry troops, I would guess that there is at least roughly 1 S-class Reaper for every world in the galaxy with the potential to produce organic lifeforms.