When Georgetown defeated Oregon State Saturday in the West Regional final of the NCAA basketball tournament, the university assured itself of at least $440,000 as its reward for gaining a berth in the final four.

But in fact, say university officials, the financial benefits that flow from such national exposure far exceed the $440,000 check from the NCAA--minus 20 percent that the Big East Conference and its seven other schools share--and they transcend basketball and athletics in general to encompass the entire university.

"People like to be associated with a program that is doing very well," says Sam McClure, Georgetown's director of corporate and foundation relations, adding that the success of the basketball team has given a major lift to the university's fund-raising efforts.

Accompanying Coach John Thompson and his team to New Orleans this weekend will be university President Rev. Timothy S. Healy and university fund-raisers who plan to use the occasion to play host to a reception for key Georgetown contributors from around the country.

"We're going to be announcing a $115 million campaign in May," said McClure.

"We're putting together a group of people, and we're offering them tickets to the game and an opportunity to meet Father Healy down in New Orleans. These are people who have contributed fairly substantial amounts of money. We'll be inviting regional directors for our campaign from around the country. We've already raised $35 million and we'd like to announce in May that we've raised $40 million.

"We'll probably have something close to 200 key people. This is a tremendous opportunity for the university to get some visibility and to bring people together who have a vital interest in the university."

Andrew Kentz, director of Georgetown's alumni fund, says contributions this year are running 32 percent ahead of last year's pace and that he has no doubt that basketball is one of the major reasons.

"At this rate we'll raise between $1.75 and $1.8 million in our fund," said Kentz. "That would be about a $400,000 increase over last year."

Traditionally, said Kentz, March is one of the slower months for Georgetown's alumni fund drive with an average of about 20 gifts a day. This year the average is 80, he said.

Moreover, said Kentz, the Hoya Hoops Club--a basketball booster organization--has raised a record $70,000 this year. Hoyas Unlimited, a booster program for all other sports, has surpassed its goal of $100,000 for the year.

"When the team travels it gives us a reason to get the alumni together," said Kentz. " . . . They may get to meet Coach Thompson and the team, and they get an opportunity to hear about the university, not only about basketball, but about other things we are doing that are not so much in the news."

For home games at Capital Centre, said McClure, "we use that as a vehicle for bringing people out and having dinner and drinks after the game and meeting with the president of the university . . . If you go back far enough at Georgetown, people would not have wanted to come out and watch a basketball game anywhere."

In the past two weeks, Georgetown and Capital Centre have run a vigorous newspaper advertising campaign for 1982-83 season tickets. Although no specific figures were available, athletic department spokesman Jim Marchiony said Georgetown was "pleased with the response." Georgetown sold about 6,300 season tickets this year in its first season at Capital Centre.

William R. Stott Jr., vice president and dean of student affairs at Georgetown, said the success of the basketball program "serves as a campus rallying point."

Sunday at 3:15 p.m., about 24 hours after Georgetown gained a spot in the final four, the first students began camping out at the door of McDonough Arena to be assured of being able to purchase tickets for New Orleans when the first of Georgetown's allotment of 2,500 went on sale at noon yesterday.

By dawn yesterday, the crowd had grown to approximately 350, who had camped out in line all night. By dusk, Georgetown's allotment of tickets was sold out.