You could figure out a Prime number by the help of its factors. If it has only 2 factors which are 1 and number itself, then it is prime.
You can figure out the number is prime by dividing it by all numbers between that and 1. If it gets divided then it is not prime.
With difficulty.
You would need to check for divisibility by all integers up to (and including) the square root of the number.
But you do know the factors of prime numbers. Every prime number has two factors: one and the number itself.
Prime squares
Yes. It is divisible only by itself, and 1. All prime numbers are ONLY divisible by themselves, and 1. The list begins, 1,2,3,5,7.... maybe it could be fun for you to figure out the numbers between there and 257.
No.
The only even prime number is 2.
It could be odd numbers, it could be prime numbers.
It could be odd numbers, it could be prime numbers.
No.
No.
A prime number has only 2 factors which are 1 and itself. Composite numbers are everything else except 1 and 0. 1 and 0 are neither prime, nor composite.
11 and 7 have a difference of 4.
No. Those two non-prime numbers will be factors, so it could not be prime.