repquota -uga Results *Hacked?

RH 7.3
Ensim 3.1

I might be way off here but I noticed something today when I was vailidating my quotas.  A few users in the quota area are not in my group or passwd files see below.  I have listed what I feel are possibly groups made by my system being hacked?

The only reason I say is the obvious #666 and in my group file these do not exist

***************repquota -uga

                        Block limits                File limits
Group           used    soft    hard  grace    used  soft  hard  grace
----------------------------------------------------------------------
#502      --     868       0       0            158     0     0
#575      --      36       0       0             11     0     0
#666      --    1048       0       0            257     0     0
#80       --     116       0       0             29     0     0
#96       --      48       0       0             12     0     0
#526      --     212       0       0             53     0     0

Any Ideas on whay this could be and how I would remove them?