This is a very simple thing to do but it often takes a lots of time to find.

Here is how to get group details if you have a group id:

$group = groups_get_group( array( 'group_id' => $group_id ) );

You could also add ‘load_users’ => true in the array if you want the members.

Below is an example of the output:

BP_Groups_Group Object
(
    [id] => 15
    [creator_id] => 1
    [name] => Demo Group
    [slug] => demo-group
    [description] => This is a test group description.
    [status] => public
    [enable_forum] => 1
    [date_created] => 2013-06-19 11:20:04
    [admins] => Array
        (
            [0] => stdClass Object
                (
                    [user_id] => 1
                    [user_login] => johndoe
                    [user_email] => johndoe@dessky.com
                    [user_nicename] => johndoe
                    [is_admin] => 1
                    [is_mod] => 0
                )
 
        )
 
    [total_member_count] => 4
    [last_activity] => 2013-06-20 11:20:04
    [is_member] => 1