- Sum of Digits
java
public class Main {
public static void main(String[] args) {
int num = 1234, sum = 0;
while (num > 0) {
sum += num % 10;
num /= 10;
}
System.out.println("Sum = " + sum);
}
}
output
2. Count of Digits
java
public class Main {
public static void main(String[] args) {
int num = 1234, count = 0;
while (num > 0) {
count++;
num /= 10;
}
System.out.println("Count = " + count);
}
}
output
3. Reverse a Number
public class Main {
public static void main(String[] args) {
int num = 1234, rev = 0;
while (num > 0) {
int digit = num % 10;
rev = rev * 10 + digit;
num /= 10;
}
System.out.println("Reverse = " + rev);
}
}
output

