Think of a number, write down its name, and add up the values of the letters (A=1, B=2, etc.). For example:

4 -> FOUR -> F(6) + O(15) + U(21) + R(18) -> 60

80 is the smallest number that is diminished by this procedure:

80 -> EIGHTY -> E(5) + I(9) + G(7) + H(8) + T(20) + Y(25) -> 74

Curiously, it’s also the smallest such number in Spanish:

80 -> OCHENTA -> O(16) + C(3) + H(8) + E(5) + N(14) + T(21) + A(1) = 68

(Remember that Spanish uses 27 letters, with ñ in the 15th position.)

(Thanks, Claudio.)