diff --git a/addons/web/static/src/js/view_form.js b/addons/web/static/src/js/view_form.js
index c5a2fbb4dc6..aa19916c260 100644
--- a/addons/web/static/src/js/view_form.js
+++ b/addons/web/static/src/js/view_form.js
@@ -273,6 +273,10 @@ openerp.web.FormView = openerp.web.View.extend( /** @lends openerp.web.FormView#
             if (field in argument_replacement) {
                 return argument_replacement[field](i);
             }
+            // literal number
+            if (/^-?\d+(\.\d+)?$/.test(field)) {
+                return Number(field);
+            }
             // form field
             if (self.fields[field]) {
                 var value = self.fields[field].get_on_change_value();
diff --git a/addons/web/static/test/onchange.js b/addons/web/static/test/onchange.js
index 9f047f33d93..8074c755bd3 100644
--- a/addons/web/static/test/onchange.js
+++ b/addons/web/static/test/onchange.js
@@ -62,4 +62,13 @@ $(document).ready(function () {
         var result2 = f.parse_on_change("on_str('foo')", {});
         deepEqual(result2.args, ['foo']);
     });
+    test('Literal number', function () {
+        var f = make_form();
+        var result = f.parse_on_change('on_str(42)', {});
+        deepEqual(result.args, [42]);
+        var result2 = f.parse_on_change("on_str(-25)", {});
+        deepEqual(result2.args, [-25]);
+        var result3 = f.parse_on_change("on_str(25.02)", {});
+        deepEqual(result3.args, [25.02]);
+    });
 });