I suspect you are running your SQL as a script. In that mode, we try to make output look exactly like SQL*Plus, so the (non) scientific notation option doesn't apply there.
When running scripts, you can do something similar by adding this at the top of your script:
set numformat 999999999999999999
(add more digits if your numbers are longer than that, otherwise you'll get ####### instead).
If you are just running a single select statement, it's really better to run it with F9 (as a statement) instead of F5 (as a script). It's faster and uses less memory.