Functions vs methods in Scala

I am watching Runar Bjarnason present Functional Programming for Beginners, and at 14:45 he defines a method:

def isDivisibleBy(k: Int): Int => Boolean = i => i % k == 0

and a function:

val isEven = isDivisibleBy(2)

What are the pros and cons of defining isEven as a function rather than a method?

I have read Scala Functions vs Methods as well as Difference between method and function in Scala, and I understand the semantic differences, but I wonder if there's some deeper reason in this case why a function might or might not be preferable to using a method:

def isEven = isDivisibleBy(2)