Can you replace the question mark with the number to complete the…

Can you replace the question mark with the number to complete the series, provided the pair of numbers exhibits a similar relationship ? ? : 4623 :: 9 : 647

This problem repeats another one in the library (at most with different numbers), so it's left out of browsing.

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · train #47646