SQL & PL/SQL

Hi, I am trying to format a number from a view but it isn't working. Any help is appreciated.

desc C_AMG

Name Null? Type
----------------------------------------- -------- -------------------------


GI50 VARCHAR2(40)

This works and returns data. However I would like the number formatted and it isn't by default:
CREATE or REPLACE FORCE VIEW test_view_jj AS SELECT
(TO_NUMBER(E.GI50)) GI50
from C_AMG E;

So I tried to format it:

CREATE or REPLACE FORCE VIEW test_view_jj AS SELECT
(TO_NUMBER(E.GI50, 999999999.99)) GI50
from C_AMG E;

select gi50 from c_amg_view_to_number
*
ERROR at line 1:
ORA-01722: invalid number