Including an interesting breakdown by @adrian_b of how the article jumps to conclusions not published in the paper.
In the range of 4-50 bits. FYI, classical computers have been used to crack RSA up to around 800 bits. Though if quantum computers can be scaled, the difficulty should scale less exponentially than with classical computers.
So 5,000 qbits to crack a 50 bit prime key. That’s an interesting factor. Assuming a similar scale, 204,800 qbits would crack RSA 2048 keys. I’m curious why it scales to needing “millions” according to those researchers.