What is a Merchant Code and how can I get by scanning a business's QR?

[clmnin]

I assumed if I scan a merchant's QR I can get the merchant code. But I'm unable to.

Consider this upi uri scanned form a merchant

upi://pay?pa=phonenumber@okbizaxis&pn=BusinessAccount&mc=5010&aid=uGICAgIC9_dC3Vw&tr=BCR2DN6TQXL7FGLM

Is mc the merchant code? I tried using that but I get an error

No payment account registered on Google Pay