How many bells in a bell tower?

There is no fixed number, but for a Carilllon, which is a tuned musical instrument operated from some form of Keyboard, the minimum is set by musicologists at 23 bells. a good memory-jogger is the time-honored 23Rd Psalm.  By the way many of the Psalms in the Bible were originally intended to be lyrics for Hymns, there was a form of musical instrument ( not bell type) called a Psaltery for this purpose.  While we are at it, I understand Bells are NOT used in Temples or Synagogues of the Jewish Faith.  There are no wedding bells in Synagogues!