Immediately after his election or appointment, the state auditor shall execute and deliver to the governor a bond to the state in the sum of fifty thousand dollars, to be approved by the governor, conditioned for the faithful performance of all the duties required or which may be required of him by law, whether as state auditor or in any capacity in which he may be required to act ex officio by virtue of being state auditor; which bond shall be renewed every two years, and as much oftener as the governor may require. The state auditor’s bond shall be a surety bond and entered into with a surety company or companies authorized to do business in this state. The cost of said bonds shall be paid by the state. If the governor be in doubt as to the solvency of the surety company or companies on the bond of the state auditor, he may require further evidence of the solvency of such surety company or companies. After the legality of said bond shall have been passed upon by the attorney general it shall be submitted to the governor for his approval. If the governor approve the bond, he shall endorse thereon such approval and its date, and deliver the same to the secretary of state to be filed and recorded in his office.