BGP cluster ID

Router
router bgp 64615
 no synchronization
 bgp router-id 10.74.50.244
bgp cluster-id 2887698805
 bgp log-neighbor-changes
 network 10.74.50.240 mask 255.255.255.252
 network 10.74.50.244 mask 255.255.255.255
 network 10.74.50.0 mask 255.255.255.0
 network 172.30.201.117 mask 255.255.255.255
 network 172.30.205.212 mask 255.255.255.252
 neighbor 172.30.205.214 remote-as 13321
 neighbor 172.30.205.214 description AT&T
 neighbor 172.30.205.214 route-map ADVERTISE_LOCAL_ONLY out


Router#show ip bgp ?
  A.B.C.D          IP prefix <network>/<length>, e.g., 35.0.0.0/8
  A.B.C.D          Network in the BGP routing table to display
  cidr-only        Display only routes with non-natural netmasks
  community        Display routes matching the communities
  community-list   Display routes matching the community-list
  dampened-paths   Display paths suppressed due to dampening
  filter-list      Display routes conforming to the filter-list
  flap-statistics  Display flap statistics of routes
  inconsistent-as  Display only routes with inconsistent origin ASs
  ipv4             Address family


I have a cluster-id configured.  I think it may be legacy.  When I do a show ip bgp ? - cluster-id is not present.  

How can I verify if the cluster-id is still being used or not being used, and why is this still here?  Isn't the command "neighbor 10.x.x.x cluster-id x.x.x.x" needed?  There is no "neighbor 10.x.x.x cluster-id x.x.x.x" under the show run.