www.internap.com has no MX records.
Question and response
Question
dig www.internap.com. MX
Answer
The response has no answer records.
Authority
internap.com. 600 SOA ns-a.pnap.net. hostmaster.pnap.net. 2020062575 3601 1800 604800 600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0