Yes you can..
man vsftp
vsftpd.conf may be used to control various aspects of vsftpd's behaviour.
Code:
ftp_data_port
The port from which PORT style connections originate (as long as the poorly named connect_from_port_20 is enabled).
Default: 20
listen_port
If vsftpd is in standalone mode, this is the port it will listen on for incoming FTP connections.
Default: 21