PARIS : Princess Doan de Champassak , born Barbara Hutton , generally believed top be the richest woman in the world , with her husband Prince Doan de Champassak ...husband No. 7, in Paris where he had just received the Laotian national Order of the Million Elephants and White Parasol . Her previous husbands have been :- Prince Alexis Mdivani , Count Kurt von Haughwitz Reventlow , Cary Grant , Prince Igor Troubetzkoy , Porfirio Rubirosa and Baron Gottfied von Cramm . 21st november 1964