Question 1

What is the smallest prime number?

Accepted Answer

The smallest prime number is 2, which is also the only even prime number.

Question 2

Are all odd numbers prime?

Accepted Answer

No, not all odd numbers are prime. For example, 9 is odd but not prime because it can be divided by 3.

Question 3

Why is 1 not considered a prime number?

Accepted Answer

1 is not considered a prime number because it only has one positive divisor, itself. A prime number must have exactly two distinct positive divisors: 1 and itself.

Question 4

Can prime numbers be negative?

Accepted Answer

No, prime numbers cannot be negative. They are defined only in the set of natural numbers, which are positive integers greater than 1.

Question 5

How are prime numbers used in cryptography?

Accepted Answer

Prime numbers are used in cryptography to encrypt data. They form the basis of various encryption algorithms, such as RSA, which relies on the difficulty of factoring the product of two large prime numbers.

Question 6

Is there a largest prime number?

Accepted Answer

There is no largest prime number. Prime numbers are infinite, as proven by Euclid over 2000 years ago.