Java: Print all prime factors of a given number

Last update on March 11 2025 11:05:59 (UTC/GMT +8 hours)

Prime Factors of Number

Write a Java program to print all the prime factors of a given number.

Sample Solution:

Java Code:

import java.util.*;
class solution {
    public static void main(String[] args)
    {   
      Scanner sc=new Scanner(System.in);
      Scanner scan = new Scanner(System.in);
      System.out.print("Input a number: ");
      int n = scan.nextInt();
	  if (n>0)
	  {	
       while (n%2==0) 
        { 
            System.out.print(2 + " "); 
            n /= 2; 
        } 
  
        for (int i = 3; i <= Math.sqrt(n); i+= 2) 
        { 
            while (n%i == 0) 
            { 
                System.out.print(i + " "); 
                n /= i; 
            } 
        } 
        if (n > 2) 
            System.out.print(n); 
       }
	}
}

Sample Output:

Input a number:  78
2 3 13

Flowchart:

For more Practice: Solve these Related Problems:

• Write a Java program to recursively factorize a number into its prime factors and print each factor.
• Write a Java program to generate the prime factors of a number using trial division and count their frequencies.
• Write a Java program to factorize a number recursively and then compute the product of its unique prime factors.
• Write a Java program to print all prime factors of a number and then sort them in ascending order.

Java Code Editor:

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