betrothed numbers
pairs of positive integers such that the sum of the proper divisors of either number is one more than the other number
en-GB/bɪˈtɹəʊðd ˈnʌmbəz/
en-US/bɪˈtɹoʊðd ˈnʌmbɚz/
pairs of positive integers such that the sum of the proper divisors of either number is one more than the other number