Qualcomm Inc. co-founder and retired chairman Irwin Jacobs was the only San Diegan to make this year’s Forbes list of the 400 wealthiest Americans.

Forbes estimated Jacobs’ wealth at $1.8 billion, ranking him No. 353 on the list.

The annual list, now in its 33rd year, shows Microsoft co-founder Bill Gates as the nation’s richest person with an estimated net lworth of $81 billion.

The No. 2 ranked richest was Gates’ buddy, Warren Buffett, chief executive of Berkshire Hathaway Cos., with a net worth of $67 billion.

Larry Ellison, the founder of Oracle who recently announced he was giving up the title of CEO, was third richest with an estimated net worth of $50 billion.

The combined net worth of the Forbes 400 totaled $2.29 trillion, which the magazine said equals the gross domestic product of Brazil.

Jacobs and his wife, Joan, have been giving away lots of their money in recent years, including this year’s pledge of $133 million to launch an innovation institute through their alma mater, Cornell University, in New York City. They also gave an additional $10 million to the San Diego Central Library, on top of an earlier gift of $20 million.