Nmap scan report for mx1.hc2781-64.iphmx.com (216.71.143.52)
Host is up (0.012s latency).
Other addresses for mx1.hc2781-64.iphmx.com (not scanned): 216.71.148.142
rDNS record for 216.71.143.52: esa.hc2781-64.iphmx.com
Not shown: 998 filtered tcp ports (no-response)
PORT    STATE  SERVICE
25/tcp  open   smtp
587/tcp closed submission

Nmap done: 1 IP address (1 host up) scanned in 7.50 seconds