ES6 in number methods

ES6 introduces several methods to Number.

The method .isFinite() is false if the number is +/- infinity or NaN.

Number.isFinite(Infinity) //false
Number.isFinite(10) // true
Number.isFinite('10') // false

.isNaN() is true if the value of the number is NaN.

.EPSILON specifies a margin of error when comparing floating point values which can't be exactly represented e.g. decimal fractions.

.isInteger(number) returns true if number is an integer.

.isSafeInteger(number) returns true if number is in the range −2^53 < i < 2^53. The result of applying an integer operator is only guaranteed to be correct if all operands and the result are safe.