IsNan() function considers certain kind of strings as number - node js

IsNan() function considers certain kind of strings as number - node js

I'm checking for integer values in node.js using IsNaN function.
Unexpectedly, this function validates the strings like 1E267146, 1E656716
, 914E6583 to be numbers, as these strings are exponential values. Any way
to work around this? Is there any other function to check for exact
integers?