This post may help to detect open port & related number services 

Detect open port and services running on server using ‘Nmap’ security scanner tool, available for windows, linux, iMac OS.

GUI (Graphical User Interface based) based ‘Nmap’ is called ‘Zenmap’.

If you wish to use the CLI version of Nmap, or want to learn in depth most useful commands have a look at the Nmap manual: https://nmap.org/docs.html.

Here we have a list of some of the most popular ports number and associated services name list.

20 FTP data (File Transfer Protocol)21 FTP (File Transfer Protocol)22 SSH (Secure Shell)
23 Telnet
25 SMTP (Send Mail Transfer Protocol)
43 whois53 DNS (Domain Name Service)
68 DHCP (Dynamic Host Control Protocol)
80 HTTP (HyperText Transfer Protocol)
110 POP3 (Post Office Protocol, version 3)
137 NetBIOS-ns 138 NetBIOS-dgm 139 NetBIOS
143 IMAP (Internet Message Access Protocol)
161 SNMP (Simple Network Management Protocol)
194 IRC (Internet Relay Chat)
220 IMAP3 (Internet Message Access Protocol 3)
443 SSL (Secure Socket Layer)
445 SMB (NetBIOS over TCP)
1352 Lotus Notes
1433 Microsoft SQL Server
1521 Oracle SQL
2049 NFS (Network File System)
3306 MYSQL
4000 ICQ
5800 VNC 5900 VNC
8080 HTTP