--- title: reverseNumber tags: math,string,beginner --- Reverses a number. - Use `Object.prototype.toString()` to convert `n` to a string. - Use `String.prototype.split('')`, `Array.prototype.reverse()` and `String.prototype.join('')` to get the reversed value of `n` as a string. - Use `parseFloat()` to convert the string to a number and `Math.sign()` to preserve its sign. ```js const reverseNumber = n => parseFloat(`${n}`.split('').reverse().join('')) * Math.sign(n); ``` ```js reverseNumber(981); // 189 reverseNumber(-500); // -5 reverseNumber(73.6); // 6.37 reverseNumber(-5.23); // -32.5 ```