User blog comment:Primussupremus/A number that uses ordinals./@comment-5529393-20170419050914

Assuming you are talking about the fast growing hierarchy then

F_omega(3) = F_3(3) = F_2(F_2(F_2(3))) = F_2(F_2(24)) = F_2(402,653,184) = 402653184 * 2^402653184 > 10^121210694