It is 53 and here are some more
53, 59, 61, 67, 71, 73, 79, 83, 89, 97
no
Yes.
No, it is composite.
21 is not a prime number.
composite.
53
53 is the next one.
It is composite.
54 is a composite number, not prime, because 2, 3, and 6 also go into it.
It is 47.
No, two.
No. 59 is a prime number.