Fair And Sqr Ex with JS

FairSqr.js

var reverseNum = function(num) { return num.toString().split('').reverse().join(''); };
var sqrt = function(num) { return Math.sqrt(num); };
var msqrt = _.memoize(function(num){ return sqrt(num); });
var isFair = function(num) { return num == reverseNum(num);};
var isSqr = function(num) { return (msqrt(num) % 1) == 0;};
var sqrFair = function(num) { 
   var _sqrt = msqrt(num);
   return isFair(_sqrt);
};

var isSqrAndFair = function(num) { return isFair(num) && isSqr(num) && sqrFair(num); }

var getSqrAndFair = function(listOfNumbers) {
   return _.filter(listOfNumbers, function(it){ return isSqrAndFair(it)})
}


getSqrAndFair([9, 12, 344,232,3465,56756])