Which app use Port 631 IPP

Hello,

I have a doubt, i know that port 631 its the cups service or ipp, but I don't have any printer installed or configured, I recently format my Mac with the restore option because a trojan horse, but know with only installed pages and numbers I made portscanning with the network utility and without any program open I have open the port 631 ipp, and making a netstat it appears localhost.ipp on local address and *.* on foreign address.

My question is , which service or program could be using that port if I didn't configure any printer or shared printer on the lan ?

Usually its not open but I am worry when it is

Thanks