Googology Wiki
Googology Wiki

Googoloctiplex in zeroes

Googoloctiplex, googoloktoplex, or googolplexplexplexplexplexplexplexplex is equal to E100#9 = EEEEEEEEE100  in Hyper-E notation.[1]

It is also equal to \(^{10}10^{2}\) = 101010101010101010100, or one followed by googolseptiplex (googolplexplexplexplexplexplexplex) zeros. It is 1010101010101010100+1 digits long.

Writing down the full decimal expansion would take 1010101010101010100-6 books of 400 pages each, with 2,500 digits on each page (except for the first, which would have 2,501).


The name of this number is based on Latin infix "octi-" and the number "googolplex".

Approximations in other notations

Notation Approximation
Up-arrow notation \(57 \uparrow \uparrow 10\)
Chained arrow notation \(57 \rightarrow 10 \rightarrow 2 \)
Hyper-E notation \(\textrm{E}100\#9\) (exact)
Hyperfactorial array notation \(13!1\)
BEAF \(\{57,10,2\}\)
Fast-growing hierarchy \(f^9_2(326)\)
Hardy hierarchy \(H_{\omega^29}(324)\)
Slow-growing hierarchy \(g_{\varepsilon_0}(10)\)


See also