%%% Abba Don

What is and what is not a number for \TeX? Adoremus magna et mirabilia opera papp\ae\ Knuth!

\beginverbatim
\ifnum 666>'0888${}-222 = 2\times32\times37={}$DCLXVI
	(all the Roman digits except the largest)\fi

\ifnum 666>"000ecce Angelus Pulcherissimus regnavit!\fi

\ifnum 666>"0000ABBA Father call I from the deepest of my s***
\else Breke kekk, breke kekk!\fi

\ifnum 11254493="ABBADDON($\aleph_0$)\fi
\endverbatim

Note that
{\tt A}, % uppercase
{\tt B}, % uppercase
{\tt c}, % lowercase
{\tt D}  % uppercase
and
{\tt e}  % lowercase
are (in some contexts) hexadecimal digits and (in those contexts) {\tt0xecce}${}=60622$
and (in some other contexts) Abbaddon is the name of the Angel of Extinction. % ]:-)\,.

\endinput

