I am an odd number.

I am less than 15.
The sum of my digits is 4.
I am a prime number.

2 answers

the odd primes less than 15 are
3,5,7,11,13
so, what do you think?
The secret is:
++++ I am a prime number. +++
3 nope
5 nope
7 nope
11 nope
13 well 1+3 = ?????