Recommend AWS EC2 instance for running GMP program

[EvaOrLew Baxter]

I am planning on using an Amazon AWS EC2 server to run my GMP program on a range of numbers. I plan to split the range and run each as a separate job on a separate core.

The 'Compute Optimized' instance appears to be suitable, but I need help on choosing a specific instance: C6g, C6gn, C5, C5a, C5n or C4. For example  C5 uses Intel Xeon E5-2666 v3 (Haswell). I looked up supported CPU types in the gmp manual but it is not clear to me if any match the C5 Haswell type. If I can use C4 then presumably 'c4.2xlarge' is appropriate because it has 8 cores.
Or, perhaps one of the 'General Purpose' types is better? Details can be found at:

https://aws.amazon.com/ec2/instance-types/

My general question is: Which EC2 instances can I use, and what is the best?

If there is a better forum to get help on this, please reply.

Thanks!
Lewis Baxter