I'm fairly certain that you can't upgrade directly from 1.9.x to 1.16.x.
You'll want to do a staggered upgrade.
For example, I'd consider upgrading to 1.10, then 1.12 > 1.14 > 1.16.
That might be more iterations than necessary. Perhaps someone else will chime in with a more elegant solution.
But each upgrade is easy and only takes a few minutes.
Just make really good backup(s) of your database before you begin.