Try this, compiled and interpreted added by sjamaan on Sat Sep 17 15:51:06 2011

;; Use -O0 to compile, else this gets completely optimized away ;)
(print "equal when read? " (= 1237940039285380274899124224 1237940039285380274899124224))
(print "equal when read and converted? " (= 1237940039285380274899124224 (string->number "1237940039285380274899124224")))