Note 2 running 4.1.2, can I delete some files I found in my download manager?

A

AC Question

Note 2 running 4.1.2

I found in my download manager numerous files named 12, 12t , 13, 13, 14, 14t all the way up to 35t, when I click on them I get a "cant find application to open" message. Am I safe to delete these? Also I rooted my phone, long story short, no PC couldnt flash to newer versions, ended up restoring the phone, havent been able to update firmware since restore. Tried Kies but didn't work. Any ideas?