Hi,
I am not sure if there something available for external use, but there is MAX_ROWID column in M_CS_TABLES which may provide you the last row id for the table. But this column is supposed to be used for internal purpose only, hence may not be recommended.
There is also ROW_NUMBER() function as part of the window functions, but that works on the data partition based on the partition criteria defined.
What is your exact requirement. Can you use an alternative like using a sequence and using it to populate a column defined in your table for row identified. You can always refer the the current value of the sequence which could be your max value for the row identifier.
Regards,
Ravi