What is an Armstrong number?
What is an Armstrong number? An Armstrong number is a number that is equal to the sum of each of the individual digits that make up the number raised to the power of the number of digits the number has. For example 153 is an Armstrong number because 153 = 1^3 + 5^3 + 3^3. 370 is an Armstrong number because 370 = 3^3 + 7^3 + 0^3. 1634 is an Armstrong number because 1634 = 1^4 + 6^4 + 3^4 + 4^4.