In this article, we will write a C language program to check whether a given number is Armstrong number or not.

## What is an Armstrong Number?

An Armstrong number is n digit number that sum of its individual digit’s power n equals that number. For example, 370 is an Armstrong number because: (3)^3 + (7)^3 + (0)^3 = 370

Here we have taken power 3 because the number 370 is 3 digit number. If we take a 4 digits number of new power will be 4 to calculate. For example, the power for the number 1667 will be 4.

Read Also:Download and Install Turbo C++ for Windows 10 (Full Installation Guide)

### C Program to Check Armstrong Number

#include <stdio.h> #include <conio.h> #include <math.h> void main() { int number, sum = 0, rem = 0, power = 0, temp, len_temp, len = 0; printf ("Enter a number to check armstrong number: "); scanf("%d", &number); temp = number; len_temp = temp; while (len_temp != 0){ len_temp /= 10; len++; } while (number != 0){ rem = number % 10; power = pow(rem, len); sum = sum + power; number = number / 10; } if (sum == temp) printf ("The given number is a valid armstrong number\n"); else printf ("The given number is not a valid armstrong number\n"); printf("Please Enetr Any Key To Continue"); getch(); clrscr(); }

**Explanation**

- First, we get an integer number from the user and store it to the number variable.
- Next, we count the length of that number.
- After that, we create a while loop to find the sum of each individual’s power bit in the given number.
- At last, we compare the sum with the given number and print the output.

This program works for a range of 1 to 1000. You can even explore more by taking a big integer.

### Conclusion

I hope this post helps you understand Armstrong’s number and its implementation in the C programming language.

Keep coding 🙂