From the best comic writer[0] how he found the answer to be a little more than 41:

    The answer to this is very simple. It was a joke.
    It had to be a number, an ordinary, smallish number,
    and I chose that one. Binary representations, base
    thirteen, Tibetan monks are all complete nonsense.
    I sat at my desk, stared into the garden and thought
    '42 will do'. I typed it out. End of story.

There is no amount of research that can take this away from me.

[0]: http://en.wikipedia.org/wiki/42_(Hitchhiker%27s_Guide_to_the...