n = int(input("Please enter a number: "))

count = 0

if n == 1:
    print("n khong la so nguyen to")
elif n == 2:
    print("n la so nguyen to")
else:
    for i in range(2, n):
        if n%i == 0:
            count = 1
            break
        else:
            count = 0
if count == 1:
    print("n khong la so nguyen to")
else:
    print("n la so nguyen to")
