The standard disclaimer on find | xargs: you should use -print0 and -0 to avoid problems with files with whitespace in their names, i.e.

   $ find -print0 | xargs -0 wc -c 2> /dev/null | tail -1

(Also, many uses of find | xargs can be replaced with -exec cmd {} \; or -exec cmd {} +, e.g.

  $ find -exec wc -c {} + 2> /dev/null | tail -1

although this isn't much faster in this case.)