Robtex

Up: 13.32.49.0/24
Can't show all results, try to descend to a more specific CIDR
Down left: 13.32.49.128/26
Down right: 13.32.49.192/26
(Some of the IP numbers are capped at 3 entries)

IP	Type	Hostname
13.32.49.221	PTR	server-13-32-49-221.nrt57.r.cloudfront.net
13.32.49.223	PTR	server-13-32-49-223.nrt57.r.cloudfront.net
13.32.49.223	A	up-live.slack.com
13.32.49.223	A	presentation-hz72146.slack.com