5173 spells Vite...

173 looks like ITE

5 in roman numerals is V.

T9 is predictive and based on a dictionary and training.

If you type "8483" on T9, your phone may offer "THUD" or "TITE" or all three, as choices.

But with a normal telephone keypad, if you dial, e.g. "(800) 555-VITE" then you will always dial "8483".

https://en.wikipedia.org/wiki/Phoneword

Also, a service port is always qualified by its protocol. There are separate port namespaces for each IP protocol that uses ports. "8483" is not a service port, until you spell it out:

  8483/tcp

  8483/udp

  8483/sctp

  8483/dccp

A TCP stream, for example, consists of a tuple:

  src:port1 dst:port2