Well obviously this kata wouldn't work if there's five or less digits in the input. (Or okay, with five digits it would give the product of all digits in the string.)

I'll leave a mention in the description that the input string has always more than five digits, so that people won't overthink about if there's going to be mischiefs.

edit: at least -> more than

Same input? The first test case checks that the result is a number, not a string for example if someone tries to return a string of numbers.

edit: In fact, that's not needed. Took it off.

It's fixed now, sorry about that. That test didn't have the correct answer. My final solution is also updated now.