One. He gives it to six Californians, thereby reducing the problem to an earlier joke...
In earlier work, Wiener [1] has shown that one mathematician can change a light bulb.
If k mathematicians can change a light bulb, and if one more simply watches them do it, then k+1 mathematicians will have changed the light bulb.
Therefore, by induction, for all n in the positive integers, n mathematicians can change a light bulb.
Bibliography:
[1] Wiener, Matthew P., <11485@ucbvax>, Re: YALBJ, 1986
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Rootbeer.
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Two, one to call Daddy, and one to get the (pick one:) mineral water/Tab.
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When it came time to pay, the skunk didn't have a scent, the deer didn't have a buck so they put the meal on the duck's bill.
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A snail because it carries it's home.
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