You can get some idea of the current number from https://docs.google.com/spreadsheets/d/1F1DzW-IZl2e9vSoaTDn-We4Uwwouxz4ldsZ6aAWSTi4/edit#gid=2121998527, but this can be edited by anyone.  I try to update the figures every couple of days.  Anyway, at the time of writing, I am seeing 185 masternodes listed, although 10 are out of action with statuses other than 'Enabled'.