How are primenumbers called that are made of 2 primenumbers?
Like 53=5 and 3, where 5 is prime and so is 3.
And is there a better method to check for such a trait than to
check for primeness and
disassemble 1113(as an example) into all possible substrings and check if those substrings are prime
So in the case 1113(which is NOT prime) check
1 and 113 -> 1 is not prime
11 and 13 -> 11 and 13 are both prime
111 and 3 -> 111 is not prime
Edit (expressed more mathematicly):
For some primenumber $N$ i want to find $p_1$ and $p_2$(where $p_i$ is a primenumber), such that $N=p_1\times 10^n + p_2$ for some natural $n$.
A general method for $k$ substrings is also appreciated.