SQL & PL/SQL :: Sort A Comma Separated String?

I have a requirement to sort a comma seperated string. For example if I pass '1234,432,123,45322,56786' as string, then it should return '123,432,1234,45322,56786', after sorting the numbers inside the string.

I have done it creating Global Temporary table. Is there a way without creating the Temp table. I understand I can write the whole logic to sort and append the string, but if there is any direct way.

CREATE GLOBAL TEMPORARY TABLE TEMP_TAB(COL1 VARCHAR2(100)) ON COMMIT DELETE ROWS;
CREATE OR REPLACE FUNCTION func_sort_string(pi_string IN VARCHAR2, pi_delimiter IN VARCHAR2 DEFAULT ',')
RETURN VARCHAR2 IS
PRAGMA AUTONOMOUS_TRANSACTION;
l_str VARCHAR2(2000) DEFAULT pi_string || ',';

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