Stirling refers to Grant as "one of the shrewdest businessmen ever to operate in Hollywood". His long-term friendship with Howard Hughes from the 1930s onward saw him invited into the most glamorous circles in Hollywood and their lavish parties. Biographers Morecambe and Stirling state that Hughes played a major role in the development of Grant's business interests, so that by 1939, he was "already an astute operator with various commercial interests". Scott also played a role, encouraging Grant to invest his money in shares, making him a wealthy man by the end of the 1930s. In the 1940s, Grant and Barbara Hutton invested heavily in real estate development in Acapulco at a time when it was little more than a fishing village, and teamed with Richard Widmark, Roy Rogers, and Red Skelton to buy a hotel there. Behind his business interests was a particularly intelligent mind, to the point that his friend David Niven once said: "Before computers went into general release, Cary had one in his brain". Film critic David Thomson believes that Grant's intelligence came across on screen, and stated that "no one else looked so good and so intelligent at the same time".  After Grant retired from the screen, he became more active in business. He accepted a position on the board of directors at Faberge. This position was not honorary, as some had assumed; Grant regularly attended meetings and travelled internationally to support them. His pay was modest in comparison to the millions of his film career, a salary of a reported $15,000 a year. Such was Grant's influence on the company that George Barrie once claimed that Grant had played a role in the growth of the firm to annual revenues of about $50 million in 1968, a growth of nearly 80% since the inaugural year in 1964. The position also permitted use of a private plane, which Grant could use to fly to see his daughter wherever her mother, Dyan Cannon, was working.  In 1975, Grant was an appointed director of MGM. In 1980, he sat on the board of MGM Films and MGM Grand Hotels following the division of the parent company. He played an active role in the promotion of MGM Grand Hotel in Las Vegas when opened in 1973, and he continued to promote the city throughout the 1970s. When Allan Warren met Grant for a photo shoot that year he noticed how tired Grant looked, and his "slightly melancholic air". Grant later joined the boards of Hollywood Park, the Academy of Magical Arts (The Magic Castle, Hollywood, California), and Western Airlines (acquired by Delta Air Lines in 1987).

Answer this question "Are there any other interesting aspects about this article?" by extracting the answer from the text above.
". His long-term friendship with Howard Hughes from the 1930s onward saw him invited into the most glamorous circles in Hollywood and their lavish parties.