SCN_TO_TIMESTAMP
SCN_TO_TIMESTAMP function takes SCN as argument and return the timestamp associated with that SCN. It is helpful if you want to know when a row has been updated.
Example:
SQL> select id,name,DBMS_ROWID.ROWID_BLOCK_NUMBER(rowid),ora_rowscn,scn_to_timestamp(ora_rowscn) from emp where id=2;