diff --git a/pkgs/racket-test-core/tests/racket/print.rktl b/pkgs/racket-test-core/tests/racket/print.rktl
index 3e6d4cad35..e7a7d0b06d 100644
--- a/pkgs/racket-test-core/tests/racket/print.rktl
+++ b/pkgs/racket-test-core/tests/racket/print.rktl
@@ -62,6 +62,7 @@
   (ptest "'|apple banana|" '|apple banana|)
   (ptest "'||" '||)
   (ptest "'#:apple" '#:apple)
+  (ptest "'#%apple" '#%apple)
   (ptest "\"apple\"" "apple")
   (ptest "#\"apple\"" #"apple")
   (ptest "#rx\"apple\"" #rx"apple")
diff --git a/racket/src/cs/expander.sls b/racket/src/cs/expander.sls
index 2f72f48560..9d3463f5e1 100644
--- a/racket/src/cs/expander.sls
+++ b/racket/src/cs/expander.sls
@@ -208,7 +208,7 @@
   ;; the printer needs to check whether a string parses as a number
   ;; for deciding wheter to quote the string
   (set-string->number?! (lambda (str)
-                          (not (not (1/string->number str 10 'read)))))
+                          (number? (1/string->number str 10 'read))))
 
   ;; `set-maybe-raise-missing-module!` is also from the `io` library
   (set-maybe-raise-missing-module! maybe-raise-missing-module))