diff --git a/build/tools/repopick.py b/build/tools/repopick.py
index 0132124..beda846 100755
--- a/build/tools/repopick.py
+++ b/build/tools/repopick.py
@@ -260,10 +260,10 @@
     change_numbers = []
     if args.topic:
         reviews = fetch_query(args.gerrit, 'topic:{0}'.format(args.topic))
-        change_numbers = sorted([str(r['number']) for r in reviews])
+        change_numbers = sorted([str(r['number']) for r in reviews], key=int)
     if args.query:
         reviews = fetch_query(args.gerrit, args.query)
-        change_numbers = sorted([str(r['number']) for r in reviews])
+        change_numbers = sorted([str(r['number']) for r in reviews], key=int)
     if args.change_number:
         for c in args.change_number:
             if '-' in c: