pacloudflare.com has no MX records.
Question and response
Question
dig pacloudflare.com. MX
Answer
The response has no answer records.
Authority
pacloudflare.com. 1800 SOA brenda.ns.cloudflare.com. dns.cloudflare.com. 2397481231 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0