The duration of  hospitalization is generally either 2 days and 1 night or 3 days and 2 nights.

The hospitalization fee is approximately  \900,000-\1,200,000 .
Although you are likely to be charged \300,000-\400,000 (30% ,  as with most  Japanese health insurance organizations), the out-of-pocket medical costs can eventually be \100,000-\150,000 if a medical insurance  claim for reimbursement is made.
A social insurance office or  city office should be contacted for details.