"Corporate central credit union" means a cooperative organization whose members consist primarily of other credit unions and whose purposes are:
(a) To accumulate and prudently manage the liquidity of its member credit unions through interlending and investment services;
(b) To act as an intermediary for member credit unions to the payment systems and facilitate funds transfers between its member credit unions and other financial institutions or their agents;
(c) To obtain liquid funds from other credit union organizations, financial intermediaries and other sources; and
(d) To perform such other financial services that benefit its member credit unions and that are authorized in writing by the Director of the Department of Consumer and Business Services.