does-my-number-look-big-in-this.js

// A Narcissistic Number (or Armstrong Number) is a positive number which is the sum of its own digits, each raised to the power of the number of digits in a given base. In this Kata, we will restrict ourselves to decimal (base 10).

// For example, take 153 (3 digits), which is narcissistic:

//     1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153
// and 1652 (4 digits), which isn't:

//     1^4 + 6^4 + 5^4 + 2^4 = 1 + 1296 + 625 + 16 = 1938
// The Challenge:

// Your code must return true or false (not 'true' and 'false') depending upon whether the given number is a Narcissistic number in base 10.

// This may be True and False in your language, e.g. PHP.

// Error checking for text strings or other invalid inputs is not required, only valid positive non-zero integers will be passed into the function.

function narcissistic(value) {
    const num = value.toString().split('').map(Number);
    const pow = num.length;
    const sum = num.reduce((total, item) => total + Math.pow(item, pow), 0);
    return sum == value;
}