Ten.
10 to the 60th power
A googol is 10 to the power of 100, and a googolplex is 10 to the power of a googol (or 10 to the power of 10^100). A googolplexian is 10 to the power of a googolplex, which is a number so large it's practically incomprehensible. The number of zeros in a googolplexian would be a 1 followed by a googolplex number of zeros.
A googol is 10 to the power of 100, which is a 1 followed by 100 zeros. A googolplex is 10 to the power of a googol, or 10^10^100. A googolplexplex is 10 to the power of a googolplex, or 10^10^(10^100). Adding more "plexes" exponentially increases the number of zeros, so a googolplexplexplexplex would have an incomprehensibly large number of zeros.
One hundred zeroes.
10 to the power of 10 to the power of 100 zeros! EDIT: It has 100 zeros. 10^10^100 is a googolplex (10^googol)
7
28 zeros
Factorial 10 to the power factorial 10 will have 7257600 zeros.
1060 has 60 zeros.
180 times 10 to the power of 4 is 1,800,000 which has five zeros in it
Ten.
10 to the 60th power
Twenty.
100.
A googlplex is 1 with a googol zeros after it. A googol is 10 to the power of 100.
7 zero