Two [or more] numbers are said to be relatively prime or coprime if they have no factor in common [other than 1]. They need not be prime numbers.
Equivalently, a set of numbers is relatively prime if and only if their GCF is 1.
Thus, 2*7 = 14 and 3*5 = 15
Neither 14 nor 15 is a prime but they are relatively prime since they do not have a factor in common.
Any prime number is relatively prime to any other prime number.
A number is relatively prime to another number or set of numbers when their GCF is 1.
It can be. 16 is relatively prime with 25.
It can be. 27 is relatively prime to 28.
41 is relatively prime.
A number cannot be relatively prime number by itself. It can only be relatively prime in the context of (relativeto) another number. That requires the two numbers not to have any prime factors in common.
The numbers are relatively prime, or co-prime.
no three is not a prime number
Two numbers are relatively prime if they have no factor in common. But a single number cannot be relatively prime.
13 and 4 are relatively prime.
13 and 24 are relatively prime.
They are not relatively prime. To be relatively prime, the only common factor they could have would be the number 1. Both also have the number 3 as a common factor, so they are not relatively prime.