diff --git a/scrapy/pipelines/files.py b/scrapy/pipelines/files.py
index 2959179b8..bbe4b9558 100644
--- a/scrapy/pipelines/files.py
+++ b/scrapy/pipelines/files.py
@@ -260,7 +260,7 @@ class FTPFilesStore(object):
         u = urlparse(uri)  
         self.port = u.port
         self.host = u.hostname
-        self.port = int(u.port or '21')
+        self.port = int(u.port or 21)
         self.username = u.username or self.FTP_USERNAME
         self.password = u.password or self.FTP_PASSWORD
         self.basedir = u.path.rstrip('/')
@@ -512,4 +512,4 @@ class FilesPipeline(MediaPipeline):
     def file_path(self, request, response=None, info=None):
         media_guid = hashlib.sha1(to_bytes(request.url)).hexdigest()
         media_ext = os.path.splitext(request.url)[1]
-        return 'full/%s%s' % (media_guid, media_ext)
\ No newline at end of file
+        return 'full/%s%s' % (media_guid, media_ext)