How many demisemiquavers are there in a double dotted semibreve?

A double dotted semibreve (whole note) lasts for 6 beats. A demisemiquaver (sixteenth note) is 1/16 of a whole note, meaning there are 16 demisemiquavers in a whole note. Therefore, in a double dotted semibreve, there are 16 demisemiquavers.