(100 raise to power 100) - 1 is divible by ???????????????

It is divisible by 9 and all other multiples of 9 and submultiples of 9

no, the ans provided by dhruv is correct to some extent i'll give it 1 out of 5.
my sol:
you can rewrite your question as:
100^100-1^100
now,
theres a formula---(h^n-1)/(h-1)=n.1^(n-1)
here h=100,n=100

to bring your question in formula form;divide and multiply 100^100-1^100
by h-1 that is 100-1 which is 99
now your equation looks as follows(100^100-1^100)/99)*99
which will be equals to:=100.1^(100-1)
which is nothing but 100,
hence th soln will be 9900.
hence div by 99 and 100.