Banks shall be invested with the right and power to receive money on deposit, allowing therefor to the depositor, if the corporation chooses so to contract, interest at a rate not in excess of the maximum rate of interest authorized by the laws of the United States or by regulations issued under authority of these laws to be paid on deposits by member banks of the federal reserve system or by nonmember banks whose deposits are insured by the federal deposit insurance corporation, whichever is lower.