Solved by tom in post #2 
              
              
                The seed is a signed 64 bit integer on the C++ side, so the maximum is (1<<63)-1. 
You could use “13248873089935215612 & ((1<<63)-1)” if you wanted to. 
I tend to be cautious about trying to be clever with random seeds, I’m not certain that your seed is any better than, say, 42. 
Best regards 
Thom…