Divisors, Count of Divisors and Prime Numbers

What is a Divisor?

A divisor is a number that divides another number completely without leaving a remainder.

For example:
Divisors of 10 → 1, 2, 5, 10

Flowchart

Flowchart Logic

1. Start the program
2. Initialize the number (Num = 100)
3. Set divisor value (Div = 2)
4. Check if Div is less than Num
5. If true:
6. Check if Num is divisible by Div
7. If yes, print the divisor
8. Increase Div by 1
9. Repeat the process
10. Stop when condition fails

Python Code

num = 100
div = 2

while div < num:
    if num % div == 0:
        print(div)
    div = div + 1

Java Code

public class Divisors {
    public static void main(String[] args) {
        int num = 100;
        int div = 2;

        while (div < num) {
            if (num % div == 0) {
                System.out.println(div);
            }
            div = div + 1;
        }
    }
}

JavaScript Code

let num = 100;
let div = 2;

while (div < num) {
    if (num % div === 0) {
        console.log(div);
    }
    div = div + 1;
}

Output

2
4
5
10
20
25
50

Find and Count Divisors of a number

Flowchart

Flowchart Logic

1. Num = 100
2. Div = 2
3. Count = 0
4. If Num % Div == 0:
5. Print divisor
6. Count = Count + 1
7. Repeat
8. Finally print Count

Python Code

num = 100
div = 2
count = 0

while div < num:
    if num % div == 0:
        print(div)
        count += 1
    div += 1

print("Total divisors:", count)

Java Code

public class DivisorsCount {
    public static void main(String[] args) {
        int num = 100;
        int div = 2;
        int count = 0;

        while (div < num) {
            if (num % div == 0) {
                System.out.println(div);
                count++;
            }
            div++;
        }

        System.out.println("Total divisors: " + count);
    }
}

JavaScript Code

let num = 100;
let div = 2;
let count = 0;

while (div < num) {
    if (num % div === 0) {
        console.log(div);
        count++;
    }
    div++;
}

console.log("Total divisors:", count);

Output

2
4
5
10
20
25
50
Total divisors: 7

What is a Prime Number?

A prime number is a number that is divisible only by 1 and itself.
For example: 2, 3, 5, 7 are prime numbers.

If a number has more than two factors, it is called a non-prime number.
For example: 4, 6, 8 are not prime.

Flowchart

Flowchart Logic

To check whether a number is prime:

1. Start with a number (let’s call it no)
2. Assume it is prime initially
3. Check divisibility from 2 up to half of the number
4. If the number is divisible by any value → it is NOT prime
5. If no divisors are found → it is PRIME

Python Code

no = int(input("Enter a number: "))

div = 2
flag = True

while div <= no // 2:
    if no % div == 0:
        print("Not Prime")
        flag = False
        break
    div = div + 1

if flag == True:
    print("Prime")

Output:

Java Code

import java.util.Scanner;

public class PrimeCheck {
    public static void main(String[] args) {

        Scanner sc = new Scanner(System.in);
        System.out.print("Enter a number: ");
        int no = sc.nextInt();

        int div = 2;
        boolean flag = true;

        while (div <= no / 2) {
            if (no % div == 0) {
                System.out.println("Not Prime");
                flag = false;
                break;
            }
            div = div + 1;
        }

        if (flag == true) {
            System.out.println("Prime");
        }
    }
}

Output:

JavaScript Code

let no = prompt("Enter a number");

let div = 2;
let flag = true;

while (div <= no / 2) {
    if (no % div == 0) {
        console.log("Not Prime");
        flag = false;
        break;
    }
    div = div + 1;
}

if (flag == true) {
    console.log("Prime");
}

Input:

Output: