A googolplex is a very large number that is equal to 10 to the power of a googol, which is a number that is equal to 10 to the power of 100. It is estimated that a googolplex is so large that it would take much longer than the age of the universe to count to it, even if you were able to count at an extremely fast rate of one number per microsecond. In other words, it would take an extremely long time to count to a googolplex.