# Time Efficient Primality Check in Python def primeCheck(n): # 0, 1, even numbers greater than 2 are NOT PRIME if n==1 or n==0 or (n % 2 == 0 and n > 2): return "Not prime" else: # Not prime if divisable by another number less # or equal to the square root of itself. # n**(1/2) returns square root of n for i in range(3, int(n**(1/2))+1, 2): if n%i == 0: return "Not prime" return "Prime"

**Here is what the above code is Doing:**

1. If n is 0, 1, or even, it’s not prime.

2. If n is odd, it’s not prime if it’s divisible by any odd number less than or equal to the square root of itself.

3. If n is odd and not divisible by any odd number less than or equal to the square root of itself, it’s prime.