[Steam API] Group Name and Type

This might not be the best place but I figure some of you here now a little bit about it.

I have the groupID64 and want to retrieve the group name.

I know the group name is written in the memberlist

https://steamcommunity.com/groups/Valve/memberslistxml/?xml=1

But a) loading the whole memberlist seams overkill b) that is not using the SteamAPI

So anyone knows how to retrieve the name via the SteamAPI
or another smaller xml table?

Further I would like to now how to get the type. Is the group public or private. Haven't seen anything about that yet.

Thank you