Check for Perfect Number in Python

Program Overview

A perfect number is a positive integer that is equal to the sum of its proper divisors (excluding itself).
Examples: 6 = 1 + 2 + 3 → Perfect 28 = 1 + 2 + 4 + 7 + 14 → Perfect 18 = 1 + 2 + 3 + 6 + 9 → Sum = 21 ≠ 18 → Not perfect

Python Code:

def is_perfect(n: int) -> bool:
    if n <= 1:
        return False
    divisors = [i for i in range(1, n) if n % i == 0]
    return sum(divisors) == n

# Read number from user
num = int(input("Enter a number: "))

# Check and display result
if is_perfect(num):
    print(f"{num} is a perfect number.")
else:
    print(f"{num} is not a perfect number.")

Sample Output:

Input: 6  
6 is a perfect number.

Input: 18  
18 is not a perfect number.

Step-by-Step Explanation:

- The program checks all proper divisors of the number
- If their sum equals the number itself, it is considered perfect
- The is_perfect function performs this check and returns the result