You have executed this command to change the size of the database buffer cache:
SQL> ALTER SYSTEM SET DB_CACHE_SIZE=2516582;
System altered. To verify the change in size, you executed this command:SQL> SHOW PARAMETER DB_CACHE_SIZENAME TYPE VALUE
------------------- ----------- ------------------ db_cache_size big integer 4194304
Why is the value set to 4194304 and not to 2516582()