Выбор из строки элементов в двойных кавычках

select d.*
from (
SELECT REGEXP_SUBSTR(str, '[^":alnum:"]+', 1, LEVEL) AS substr,
       length(trim(translate(REGEXP_SUBSTR(str, '[^":alnum:"]+', 1, LEVEL),'0123456789 ',' '))) as num_ln
  FROM (
        SELECT '"555"+2+3,3+10*("243"/"2"+"123"*"566")/2+6.6+"2666"' AS str FROM DUAL
       )
CONNECT BY LEVEL <= LENGTH(REGEXP_REPLACE(str, '[^":alnum:"]+'))
) d where d.substr is not null and
          d.num_ln is null

555
243
2
123
566
2666