ORA-00902 INVALID DATATYPE

 I encountered ORA-00902 when I was trying to run below

  ALTER TABLE TEST_TEMP ADD PARTITION BY RANGE (TESTNUMDATE) (PARTITION P201401 VALUES LESS THAN (20140201))

I also tried to modify the statement to use other fields instead but the same error occurred

  ALTER TABLE TEST_TEMP ADD PARTITION BY RANGE (TESTNUM1) (PARTITION P100 VALUES LESS THAN (101))

Here is the table structure

create table TEST_TEMP

(

  TESTPKID    VARCHAR2(7),

  TESTSTR1    VARCHAR2(10),

  TESTNUM1    NUMBER,

  TESTDATE1   DATE,

  TESTNUMDATE NUMBER

)