how to turn number into string javascript

var myNumber=120;
var myString = myNumber.toString(); //converts number to string "120"

var myNumber=120;
var myString = myNumber.toString(); //converts number to string "120"

var number = 1212
var numberString = number.toString();//converts my number that is '1212' to a string

    var num=213; 
    document.write("Output : " + num.toString());   // convert to integer string        
    document.write("Output : " + num.toString(2));   // convert to binary string       

const toNumber = str => +str;

// Example
toNumber('42');     // 42