ORA-02180: invalid option for CREATE TABLESPACE

SQL> create tablespace testing datafile '/u01/app/oracle12c/oradata/wiprodb/testing01.dbf' size 512kb;
create tablespace testing datafile '/u01/app/oracle12c/oradata/wiprodb/testing01.dbf' size 512kb
                                                                                              *
ERROR at line 1:
ORA-02180: invalid option for CREATE TABLESPACE



ORA-02180: invalid option for CREATE TABLESPACE

Note: size units are K, M, G, not KB or similar.)