Administrators, executors, guardians, trustees, and other fiduciaries of every kind and nature; insurance companies; charitable, educational, eleemosynary, and public corporations and organizations; municipalities and other public corporations and bodies; and public officials are authorized to invest funds held by them, without any order of any court, in deposits in building and loan associations or savings and loan associations which are insured under a federal deposit insurance program; and, to the extent of such insurance, such investments shall be deemed and held to be legal investments for such funds.