def is_prime(num):
    if num <= 1: 
        return False
    elif num <= 3: 
        return True
    elif num % 2 == 0 or num % 3 == 0: 
        return False
    i = 5 
    while i * i <= num:
        if num % i == 0 or num % (i + 2) == 0:
            return False 
        i += 6
    return True
for i in range(500, 600):
    if is_prime(i):
        print(i)