integer (numbers without a exponant notation) are accurate up to 15 digit. and maximum number in decimals is 17 digit
floating point arithmetic is also always not 100% accurate
but it helps to multiply and divide
if you add 2 numeric string than the result will be concatenated string
if you add a numeric and a string than the result will be concatenated string
if a number is divided by a non numeric string than it becomes NaN(Not a Number)
if a number is divided by a numeric string than it becomes a Number
you can use the global javascript function isNaN() to find out if a value is not a number
the typeof NaN is number:
infinity is returned if you calculate a number outside the largest possible number: