Dig

dig (domain information groper) gets information from DNS servers.

dig google.com Gets DNS information for the specified hostname.

You can query for specific DNS record types:

dig MX psygen.org Look for the mail exchanger records for the specified hostname.

dig NS psygen.org Look for the name server records for the specified hostname.

... and so on for any valid record type.

Short Form

You can use the short form to view just the info you need, instead of the whole record:

dig psygen.org +short
67.225.240.117

dig psygen.org ns +short
ns1.nameserver
ns2.nameserver

References:

1. dig man page