Supply is just matter of dividers here
Trading 1 XRB (former Mrai) = 10^30 RAW RaiBlocks. There was discussion about Mrai = Mxrb or XRB jayycox write several post before
Trading 1 MIOTA = 10^6 IOTA (correct me if I'm wrong, 1 IOTA is smallest unit?)

So:
IOTA 2 779 530 283 277 761 smallest units total
RaiBlocks 340 282 366 920 938 463 463 374 607 431 768 211 455 smallest units total (2^128 - 1)

For comparision:
Bitcoin 2 100 000 000 000 000 smallest units total (satoshi)
Ethereum ~ 92 574 106 000 000 000 000 000 000 smallest units circulating (wei)