One question maybe not mikrotik specific but someone will know

My mikrotik core router has his public IP address, (I own /24 subnet of public address.)

When I try nslookup for that IP it returns me reverse DNS (Address to Name) of someone else domain name.

I block all DNS requests from outside world on my core router. What can I do, and is that problem??

Tnx

my best guess is your upstream provider where you got your ip address had swiped it for a customer and did not clear it when they assigned to you. Ask them to also check their arpa file.

David