sys.objects column [Type] weird value 'ST'
Well, I don't know what ST stands for, but based on the naming convention I would have to guess it's some kind of system-generated statistic.

You could check to see if there is, by chance, some kind of text associated with the object if it is a module, e.g.:

SELECT OBJECT_DEFINITION(613577224);

SELECT definition FROM sys.all_sql_modules
  WHERE object_id = 613577224;


You could also try:

EXEC sp_help N'dbo._ST_OEA33...';


Finally, you could try to brute force discover this object in any of the catalog views. This script tries to find any view that contains a row where the object_id column is equal to that value.

CREATE TABLE #v(v sysname);

DECLARE @sql nvarchar(max) = N'', @obj int = 613577224;

SELECT @sql += N'INSERT #v 
    SELECT DISTINCT ''sys.' + name + N''' 
      FROM sys.' + QUOTENAME(name) + N' 
      WHERE [object_id] = @obj;'
  FROM sys.all_views AS v
  WHERE EXISTS 
  (
    SELECT 1 
      FROM sys.all_columns AS c
      WHERE c.name = N'object_id' 
      AND c.[object_id] = v.[object_id]
  ); 

EXEC sys.sp_executesql @sql, N'@obj int', @obj;

SELECT v FROM #v;

DROP TABLE #v;


If this yields nothing, you could expand it to include all int-based columns across all catalog views, since sometimes object_id values are stored in columns with different names, like referenced_major_id or parent_object_id, and any results here might yield clues as well.

SET NOCOUNT ON;

CREATE TABLE #v(v sysname);

DECLARE @sql nvarchar(max) = N'', @obj int = 613577224;

SELECT @sql += N'INSERT #v 
    SELECT DISTINCT ''sys.' + v.name + N''' 
      FROM sys.' + QUOTENAME(v.name) + N' 
      WHERE ' + QUOTENAME(c.name) + N' = @obj;'
  FROM sys.all_views AS v
  INNER JOIN sys.all_columns AS c
  ON v.[object_id] = c.[object_id]
  WHERE v.[schema_id] = 4
    AND c.[system_type_id] IN (56,127)
    AND v.name NOT IN (N'syscolumns')
    AND v.name NOT LIKE N'dm_fts_%'; 

EXEC sys.sp_executesql @sql, N'@obj int', @obj;

SELECT v FROM #v;

GO
DROP TABLE #v;