diff --git a/talkpython.py b/talkpython.py
index 2b8993c..3677a9a 100755
--- a/talkpython.py
+++ b/talkpython.py
@@ -17,7 +17,7 @@ def __init__(self, enclosure):
         self.length = int(enclosure.get('length'))
         self.number, original_filename = self.url.split('/')[-2:]
         self.number = int(self.number)
-        self.filename = f'{self.number}-{original_filename}'
+        self.filename = f'{self.number:04}-{original_filename}'
 
     def download(self, download_path: Path):
         print(f'Getting episode {self.url}', flush=True)