diff --git a/src/5numeric.lisp b/src/5numeric.lisp
index 3b1739a..9a90465 100644
--- a/src/5numeric.lisp
+++ b/src/5numeric.lisp
@@ -340,7 +340,7 @@ NUMCL.  If not, see <http://www.gnu.org/licenses/>.
 (defun numcl:logorc2  (&rest args) (reduce (lambda (x y) (broadcast 'logorc2  x y)) args))
 (defun numcl:logxor   (&rest args) (reduce (lambda (x y) (broadcast 'logxor   x y)) args))
 
-(defun numcl:lognot (x) (map-array 'lognot x))
+(defun numcl:lognot (x) (if (numberp x) (lognot x) (map-array 'lognot x)))