A Harshad or Niven number is a number that is divisible by the sum of its digits. 201 is a Harshad number because it is divisible by 3 (the sum of its digits.)
Belows are one-liners of Harshad in different languages.
Here’s a Ruby version written by Rafael Naufal (given on comment):
My Python version:
My PHP version:
Do you have any for one-liners?