while True: a=int(input());print(a&-~a<1 and a>1 and all(a%b for b in range(2,a))) print(a,end="\n\n")
1 2 3 4 5 6 7 8 9 20 23 28 29 31 51 127 128 1023 1024 8191
False 1 False 2 True 3 False 4 False 5 False 6 True 7 False 8 False 9 False 20 False 23 False 28 False 29 True 31 False 51 True 127 False 128 False 1023 False 1024 True 8191
Traceback (most recent call last): File "./prog.py", line 3, in <module> EOFError: EOF when reading a line