# nmap -sV 192.168.84.10

Example output:

Starting Nmap 6.47 ( http://nmap.org ) at 2015-09-24 22:40 CEST
Nmap scan report for 192.168.84.10
Host is up (0.0000090s latency).
Not shown: 996 closed ports
PORT    STATE SERVICE VERSION
25/tcp  open  http    nginx 1.6.2
80/tcp  open  http    nginx 1.6.2
111/tcp open  rpcbind 2-4 (RPC #100000)
443/tcp open  http    nginx 1.6.2

Here, 25 is a non-standard port for HTTP. Normally, 25 is used for SMTP.