A composite number whose sum of digits equal to the sum of the digits of its prime factors.Ex: 58 = 2 x 29 (5 + 8 = 12) (2+ 2 + 9 = 12)Programpublic class SmithNumbers {    public static boolean isPrime(int number) {       int loop;       int prime = 1;       for(loop = 2; loop < number; loop++) {          if((number % loop) == 0) {             prime = 0;          }       }       if (prime ... Read More

Following is the Java program which prints the kth prime factor of a number n, when k and n are given.Programimport java.util.Scanner; public class KthPrimeFactor {    public static void main(String args[]) {       int number, k, factor = 0;       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number :");             number = sc.nextInt();       System.out.println("Enter the k value :");       k = sc.nextInt();       int temp = k-1;             for(int i = 2; i< number; ... Read More

The numbers which can be expressed as the sum of positive consecutive integers are known as polite numbers.Ex: 5 = 2+3The number of ways a number can be expressed as the sum of positive integers will be the Politeness of that number.Ex: 9 = 4+5 || 2+3+4AlgorithmGet the prime factors of a number.Get the powers of prime factors greater than 2.Add 1 to all of them.Multiply them, subtract 1 from the result.Programimport java.util.Scanner; public class PolitenessOfANumber {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number");   ... Read More

Following is the Java program which prints all the sum of all the divisors of a given number.

Following is the Java program which prints all the divisors of a given number.Programimport java.util.Scanner; public class DivisorsOfNaturalNumber {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter required number :");       int num = sc.nextInt();             for(int i = 1; i

Factors are the numbers we multiply to get another number.factors of 14 are 2 and 7, because 2 × 7 = 14.Some numbers can be factored in more than one way.16 can be factored as 1 × 16, 2 × 8, or 4 × 4.A number that can only be factored as 1 times itself is called a prime number.The first few primes are 2, 3, 5, 7, 11, and 13.The list of all the prime-number factors of a given number is the prime factors of a number. The factorization of a number into its prime factors and expression of ... Read More

If the sum of the digits of a number is divisible by 3, then the number is divisible by 3.Some examples of numbers divisible by 3 are as follows.The number 85203 is divisible by 3 because the sum of its digits (8 + 5 + 2 + 0 + 3 = 18) is divisible by 3.The number 79154 is not divisible by 3 because the sum of its digits (7 + 9 + 1 + 5 + 4 = 26) is not divisible by 3.Programimport java.util.Scanner; public class DivisibleBy3 {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number :");       String num = sc.nextLine();       int digitSum = 0;             for(int i = 0; i

A number is divisible by 11 if the difference between the sum of its alternative digits is divisible by 11.i.e. if (sum of odd digits) – ( sum of even digits) is 0 or divisible by 11 then the given number is divisible by 11.Programimport java.util.Scanner; public class DivisibleBy11 {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number :");       String num = sc.nextLine();       int digitSumEve = 0;       int digitSumOdd = 0;            for(int i = 0; i

If the sum of the digits of a number is divisible by 9, then the number is divisible by 9.Some examples of numbers divisible by 9 are as follows. The number 51984 is divisible by 9 because the sum of its digits (5+ 1 + 9 + 8 + 4 = 27) is divisible by 9.The number 91403 is not divisible by 9 because the sum of its digits (9 + 1 + 4 + 0 + 3 = 17) is not divisible by 9.Programimport java.util.Scanner; public class DivisibleBy9 {    public static void main(String args[]) {       Scanner sc = new Scanner(System.in);       System.out.println("Enter a number :");       String num = sc.nextLine();       int digitSum = 0;       for(int i = 0; i

ProgramFollowing is the example to calculate the GCD of the numbers of an array.Live Demopublic class GCDOfArrayofNumbers{    public static int gcd(int a,int b){       int res = 0;       while (b > 0){          int temp = b;          b = a % b;          a = temp;          res = a;       }       return res;    }    public static void main(String arg[]){       int[] myArray = {3, 6, 8};       int result = gcd(myArray[0],myArray[1]);       for(int i = 2; i < myArray.length; i++){          result = gcd(result, myArray[i]);       }       System.out.println("Gcd of n numbers is: "+result);    } }OutputGCD of n numbers is: 1