isOdd and isEven pop up often but they and all those other packages were explicitly created for the sole purpose of boosting the author's profile.
It seems like a lot of people think they think how npm should work, while forgetting to see how npm actually works.
There's even an example of a well respected npm author that has repositories with just a few lines..
Y'all just love to hate on npm
If that were true, it would be useful for the author to actually explain that in his repo documentation. As it is, concluding that this is a joke is by far the most reasonable response.
Or you could check the lowest bit. Better to abstract away from that implementation decision. ;)