diff --git a/frigate/app.py b/frigate/app.py
index b56cb5b75..1ec476060 100644
--- a/frigate/app.py
+++ b/frigate/app.py
@@ -173,7 +173,7 @@ class FrigateApp:
 
             try:
                 with open("/config/.vacuum", "w") as f:
-                    f.write(datetime.datetime.now().timestamp())
+                    f.write(str(datetime.datetime.now().timestamp()))
             except PermissionError:
                 logger.error("Unable to write to /config to save DB state")