Nothing at all unusual about column stats (stats that aren't associated with indexes). The naming's a little odd though.
What do each of these return?
DROP STATISTICS ABCTable._dta_index_ABCTable_c_7_745806881__K2
DROP STATISTICS ABCTable._dta_stat_745806881_2_1
DROP INDEX _dta_index_ABCTable_c_7_745806881__K2 ON ABCTable
Gail Shaw
Microsoft Certified Master: SQL Server, MVP, M.Sc (Comp Sci)
SQL In The Wild: Discussions on DB performance with occasional diversions into recoverability