1 files changed, 5 insertions, 3 deletions
diff --git a/factor.scm b/factor.scm
index a5d3e8c..6d7b38d 100644
--- a/factor.scm
+++ b/factor.scm
@@ -51,9 +51,11 @@
 ;;; prime:product is a product of small primes.
 (define prime:product
   (let ((p 210))
-    (for-each (lambda (s) (set! p (or (string->number s) p)))
-      '("2310" "30030" "510510" "9699690" "223092870"
-	       "6469693230" "200560490130"))
+    (for-each (lambda (s)
+		(set! s (string->number s))
+		(set! p (or (and s (exact? s) s) p)))
+	      '("2310" "30030" "510510" "9699690" "223092870"
+		       "6469693230" "200560490130"))
     p))
 
 (define (prime:prime? n)