It is impossible for the product of two prime numbers to be prime. It is impossible for the sum of two prime numbers to be prime as long as one of the numbers isn't 2.
Chat with our AI personalities
17 and 3 are two prime numbers whose sum is 20. Their product is 51.
12
There are no such numbers.
391
The sum of three odd numbers will be odd, whether they are prime or not. The sum of three prime numbers can be even as long as one of them is 2.