gmail-smtp-in.l.google.com has address 64.233.161.26
This page provides an online version of the OS hostname and whois commands. It allows you to retrieve publicly available DNS and Whois information for any website or hostname through a single interface.
Host Info
cleantalk.org:~$ host gmail-smtp-in.l.google.com
gmail-smtp-in.l.google.com has address 64.233.161.26
gmail-smtp-in.l.google.com has IPv6 address 2a00:1450:4010:c01::1a
Whois info
cleantalk.org:~$ whois gmail-smtp-in.l.google.com
We couldn’t get the data. It may be missing or temporarily unavailable.