None, because people who glow in the dark don't need light bulbs.
Note: Topical to the Chernobyl Reactor disaster of 1984.
or
A guy who has never been hit with a dictionary.
or
1,000,001: One to change the bulb and 1,000,000 to rebuild civilization to the point where they need light bulbs again.
or
To hide in a bag of M&M's.
or