WASHINGTON — Less than a year after announcing plans to combine into a $121 billion company, Raytheon and United Technologies are officially no more — replaced by the combined entity Raytheon Technologies Corp., which kicked off trading Friday on the New York Stock Exchange.

Listed under the ticker RTX, Raytheon Technologies began selling at $51 a share. With more than 866 million shares outstanding and a market cap of $74.5 billion, that price is bound to shift in the coming days, weeks and months. To put it in perspective, Raytheon closed Thursday at $122.43 a share, and UTC closed at $91.37 a share.

With the merger, UTC shareholders owned 57 percent of Raytheon Technologies, and UTC will control eight of the 15 board seats. Tom Kennedy will serve as executive chairman, Greg Hayes as CEO and Toby O’Brien as chief financial officer.

Planned divestitures will be completed post merger, though United Technologies did complete the spinoff of HVAC, refrigeration, fire and security solutions company Carrier Global Corp., as well as elevator and escalator manufacturer Otis Worldwide Corp. Both are now trading on the S&P 500.

Amid the stock market fallout from the new coronavirus pandemic, Raytheon saw a bigger drop than most pure-play companies, likely due to the increased exposure to the commercial market that came with the merger. However, that could be short-lived, said Byron Callan of Capital Alpha Partners.

“Raytheon has been the worst-performing stock [during the crisis] because they got tied into commercial aerospace through the merger,” he told Defense News in an interview. “But going forward, that may be the most interesting [stock] of all because there will be a degree of balance.”