sql - sqlplus の sysdate に関する問題

Question

create Table dealing_record(
dealing_record_id int NOT NULL,
Transaction_number Varchar (6) NOT NULL UNIQUE,
Number_of_shares Number NOT NULL,
Amount Number (7,2) NOT NULL,
Stamp_duty Varchar(6) NOT NULL,
commission Varchar(6) NOT NULL,
Date_time SYSDATE     NOT NULL,
PRIMARY KEY(dealing_record_id));

結果

 SQL> create Table dealing_record(
2  dealing_record_id int NOT NULL,
3  Transaction_number Varchar (6) NOT NULL UNIQUE,
4  Number_of_shares Number NOT NULL,
5  Amount Number (7,2) NOT NULL,
6  Stamp_duty Varchar(6) NOT NULL,
7  commission Varchar(6) NOT NULL,
8  Date_time SYSDATE     NOT NULL,
9  PRIMARY KEY(dealing_record_id));
Date_time SYSDATE     NOT NULL,
      *
ERROR at line 8:
ORA-00902: invalid datatype

何が間違っているのですか？