-- total cursors open
SQL> select count(*) from v$open_cursor;

  COUNT(*)
----------
       287

SQL> select name,value from v$sysstat where name='opened cursors current';

NAME                                                                  VALUE
---------------------------------------------------------------- ----------
opened cursors current                                                  287

-- The following is per session
SQL> select name,value from v$system_parameter where name like 'open_cursors';

NAME
----------------------------------------------------------------
VALUE
--------------------------------------------------------------------------------
open_cursors
255