Several.
A number of people have commented on it.
There are a number of problems with the log-in system.
Several of.
I spoke with a number of them about it.
God created a number of possibilities in case some of his prototypes failed - that is the meaning of evolution. Graham Greene
A narrative is like a room on whose walls a number of false doors have been painted; while within the narrative, we have many apparent choices of exit, but when the author leads us to one particular door, we know it is the right one because it opens. John Updike
A number of images put together a certain way become something quite above and beyond what any of them are individually. Francis Ford Coppola
The world is full of a number of things, I'm sure we should all be as happy as kings. Robert Louis Stevenson
A civilization which leaves so large a number of its participants unsatisfied and drives them into revolt neither has nor deserves the prospect of a lasting existence. Sigmund Freud
After your daughter is married, there comes a number of potential sons-in-law. Russian Proverb