class Calculator(AdvancedArithmetic):
    def divisorSum(self, n):
        sum = 0
        for i in range(1, n+1):
            if n % i == 0:
                sum += i
        return sum

    public int divisorSum(int n)
    {
        int sum = 0;
        
        for(int i = n; i > 0; i--)
        {
            if(n % i == 0) sum += i;
        }
        
        return sum;
    }

interface AdvancedArithmetic {
    divisorSum(n: number): number;
}

class Calculator implements AdvancedArithmetic {
    divisorSum(n: number): number {
        let sum = 0;
        for (let i = 1; i <= n; i++) {
            if (n % i === 0) {
                sum += i;
            }
        }
        return sum;
    }
}

function main() {
   let n: number = parseInt(readLine(), 10);
   const myCalculator: AdvancedArithmetic = new Calculator(); 
   const sum = myCalculator.divisorSum(n);

    const interfaceName = "AdvancedArithmetic";
   console.log("I implemented: " + interfaceName);
   console.log(sum);
}

class Calculator(AdvancedArithmetic):
    def divisorSum(self, n):
        return sum([x for x in range(1,n+1) if n%x==0])

class Calculator(AdvancedArithmetic):
    def divisorSum(self, n):
        divisors = set()            # Divisors are unique so using set
        for i in range(1,int(n**(1/2))+1):    # Going upto sqrt of n
            if n % i == 0:
                divisors.add(i)        # Adding divisor to divisors set
                divisors.add(n/i)    # Adding Quotient to divisors set
        return int(sum(divisors))