A 'googol' is the number 1 followed by 100 zeros.  A googolplex is 10 to the power GoogolNumber, or 1 followed by a GoogolNumber of zeros.  A perfect number for folks that think size doesn't matter!

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And my 7-year old invented Gargoogolplex, which is a googolplex googolplexes!  This boy can think BIG  (well, at least he can ''speak'' BIG ;-)

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You couldn't write a googolplex if the zeros were as big as protons- it would fill the known universe! Someone actually measuring this may be a fairly rare occurrence, though.

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Would a gargantugoogolplex be gargoogolplex gargoogolplexes?  Is this suggestive of a pattern of googol prefixes and suffixes akin to metric prefixes? Like so:
 10^100 = googol
 10^googol = * - plex or googolplex
 10^googolplex = gar - or gargoogolplex
 10^gargoogolplex = gantu or gargantugoogolplex
What would come next?
 10^gargantugoogolplex = megagargantugoogolplex ???
 10^megagargantugoogolplex = fuga-gargantugoogolplex ???? ..... Then Jigglypuffplexplexplexplex!!!!
 The Jigglypuffplex = 10^fugafugafugafugafugagargoogolplexes



See ReallyBigNumbers for that...

''Shouldn't we follow the -plex convention?''
 10^N = N-plex
 10^googol = googolplex
 10^googolplex = googolplexplex
 10^googolplexplex = googolplexplexplex
''and so on. This time, we always know what comes next. --AnonymousDonor''

10^Jigglypuffplex = Jigglypuffplexplex
10^Jigglypuffplexplex = Jigglypuffplexplexplex
10^Jigglypuffplexplexplex = Jigglypuffplexplexplexplex
10^Jigglypuffplexplexplexplex = Jigglypuffmegaplex .... Then ?