Obligate [TikZ/pgf][1]-Antwort:
\documentclass{article}
\usepackage{tikz}
% \newcommand\circlearound[1]{%
% \tikz[baseline=(A.base)]\node[draw,shape=circle] (A) {#1} ;}
% besser, siehe Kommentare zur Antwort:
\newcommand\circlearound[1]{%
\tikz[baseline=(A.base)]\node[draw,shape=circle] (A) \tikz[baseline]\node[draw,shape=circle,anchor=base] {#1} ;}
\begin{document}
1 \circlearound{1} 2 \circlearound{2} 3 \circlearound{3} 4 \circlearound{4}
\end{document}
![Ergebnis][2]
[1]: http://www.ctan.org/pkg/pgf
[2]: /upfiles/zahlen-1-2-3-4.png
