Any insurance company and any health maintenance organization of this state may unite, merge or consolidate with any other company or companies of this or any other state engaged in like business and having similar corporate powers, upon such terms and conditions, including the reinsurance of the business in force, as may be approved at a meeting of the stockholders of any such company or companies of this state, called for that purpose, such approval to be by vote of stockholders owning not less than two-thirds of the shares of stock of any such company or companies of this state.