233.28.75.147.ptr.develooper.com has no MX records.
Question and response
Question
dig 233.28.75.147.ptr.develooper.com. MX
Answer
The response has no answer records.
Authority
develooper.com. 360 SOA ns.develooper.com. dnsoper.bitnames.com. 2026021994 600 600 4838400 360
Additional
. 0 OPT ; payload 4096, xrcode 0, version 0, flags 0