Extracting Value from Object Variable

I believe @Sho’s explanation will work. 

The issue is that there are two things named inputVariable: the variable you assign the input.config() to, and the input variable that you created in the left panel of the editor. 

You are conflating the two. 
Things would be less confusing if you had only one thing named “inputVariable”. Even better would be to have nothing named “inputVariable”.

Name your input variable in the left panel “boatNumber”, then you can use

const inputConfig = input.config()

const boatNumber = inputConfig.boatNumber

There are other ways to do it, but whatever method you choose, it is best to have meaningful names. 

But also keep in mind that your boat number is actually a text string and not a number.