You can use the function print_moduli_chain in this post to print all the prime factors of the extended ciphertext modulus QP in CKKS.
To control the size of the ciphertext modulus Q, you can try controling the multiplicative depth via parameters.SetMultiplicativeDepth(d); => increasing d will increase Q.
There are other ways to control P, but I assume you are not interested in that parameter.