[ES2015] Number.isNaN instead of isNaN

const result = Number('55px');

// isNaN "NaN"
console.log(isNaN(result)); // true
console.log(isNaN('I am a String!')); // true -- NOT Good

console.log(Number.NaN); // safer approach
console.log(Number.isNaN(result)); // true
console.log(Number.isNaN('I am another String!')); // false
console.log(Number.isNaN(Number.NaN)); // true

console.log(Number.isInteger(66)); // true