diff --git a/tgbot/kollagen-bot/main.py b/tgbot/kollagen-bot/main.py
index 45b1a93..1e6eb72 100644
--- a/tgbot/kollagen-bot/main.py
+++ b/tgbot/kollagen-bot/main.py
@@ -125,7 +125,7 @@ class KollagenBot:
         ]
 
         mode = ["-m", args.mode] if args.mode else []
-        num_images = ["-n", args.num_images] if args.num_images else []
+        num_images = ["-n", str(args.num_images)] if args.num_images else []
 
         with NamedTemporaryFile(suffix=".png") as ntf:
             shell_cmd_line = [