166.98.235.45.in-addr.arpa has no MX records.
Question and response
Question
dig 166.98.235.45.in-addr.arpa. MX
Answer
The response has no answer records.
Authority
98.235.45.in-addr.arpa. 86400 SOA ns1.inetgaming.com.ar. mdoval.inetgaming.com.ar. 2026021300 3600 1800 1209600 86400
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0