Are playerprefs a safe way of saving data or not??

I’ve read that playerprefs data are stored in a folder on my device(Android) but i tried looking for the folder and i found nothing of the sort. I also tried deleting all my folders but the data is still shown in my game. I’m wondering if someone could enlighten me some more because as i see it, the data is stored in the app itself.

In Android, player prefs are saved in a folder you can only access if you rooted your phone.
In windows, its saved in the registry.
In mac and Linux, idk.

NOPE!!!
MOST UNSAFE WAY THERE IS!!!
If its a big project use something else!!!
@Jadara