o36.ptr4191.dk.bestwhitepapers.net has no MX records.
Question and response
Question
dig o36.ptr4191.dk.bestwhitepapers.net. MX
Answer
The response has no answer records.
Authority
bestwhitepapers.net. 1800 SOA leia.ns.cloudflare.com. dns.cloudflare.com. 2398036064 10000 2400 604800 1800
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0