Check if a number is prime
123456789101112131415
num = int(input("Enter an integer:"))
count = 0
for i in range(1,num+1):
if num%i == 0:
count+=1
if count == 2:
print(num,"is a prime number.")
elif num == 1:
print("1 is neither prime nor composite.")
elif num<0:
print("Numbers less than zero are negative which cannot be prime numbers.")
elif count>2:
print(num,"is a composite number.")
else:
print("Invalid input.")
Python
INFO