@LuffyKun No, I didn't convert, since we don't know where the counting stopped. So he has at least a million yen in his savings account, or around nine thousand US dollars. We can safely assume that the counting of zeros didn't stop at one million since in the next bubble he seems to have lost count. And I very much doubt Mitsumune would have left the bulk of his wealth in a savings account, which has a poor rate of return.
As for the dick, the implication is that at least when flaccid, it's small, or at least smaller than the one in his previous body.