The old adage, "It's not what you know, but who you know," may ring true when it comes to the universities with the largest number of wealthy alumni.
Research firm Wealth-X compiled a list of the global universities with the largest number of living alumni worth $30 million or more, or ultra high net worth individuals, as they are called.
Read more: The Wealthiest Person in Each State
Based on Wealth-X's research, Harvard University blows the competition out of the water with 2,964 alumni worth a collective $622 billion. That's nearly twice the alumni of University of Pennsylvania, which follows with its 1,502 alumni of ultra high net worth individuals.
"Relationships and networks are so important in terms of career path success and prosperity," said David Friedman, president of Wealth-X.
Only three public universities made the top 15 list, comprised of all U.S. schools, which Friedman said has implications for educational opportunities for low-income and middle class families.
"It shows public universities have a great opportunity to build on their strategy," Friedman said about alumnae efforts.
Interestingly enough, the majority of wealthy alumni of both public and private universities were "self made."
"That speaks to the entrepreneurial spirit of individuals attending these schools who are leveraging the robust alumni networks to pull themselves into these networks," he said.
Friedman said this is the first time a group has published a report of such granular data.
Only three universities outside the U.S. -- Oxford, University of Mumbai and University of Cambridge -- made it to the top 20 list.
Here is a list of the 15 universities with the highest number of alumni worth $30 million or more.
|Harvard University; Private|
The oldest university in the country, Harvard University in Cambridge, Mass., also has the wealthiest alumni. The 2,964 ultra high net worth individuals from the Ivy League school are worth $622 billion and include 52 billionaires, the highest number of all the universities in Wealth-X's list.
|University of Pennsylvania; Private|
Based in Philadelphia, Penn's wealthiest alumni are worth a combined $242 billion.
|Stanford University; Private|
In Silicon Valley's Palo Alto, Calif., Stanford's wealthiest alumni, presumably in the tech sector, are worth $171 billion.
|Columbia University; Private|
Attending an expensive Ivy League school in one of the priciest cities in the country had better yield results for Columbia University alumni. Its wealthiest alumni, who include grad student Berkshire Hathaway CEO Warren Buffett, are worth a combined $116 billion.
|New York University; Private|
Boasting a network of business graduates from its Stern School of Business, NYU's wealthiest alumni are worth a combined $110 billion.
|University of Chicago; Private|
University of Chicago's notable alumni include Credit Suisse CEO Brady Dougan and Morningstar Inc. founder Joe Mansueto. Its wealthiest 658 living alumni are worth a combined $144 billion.
|Massachusetts Institute of Technology; Private|
The wealthiest alumni among MIT's Beavers -- engineers in nature and the school's mascot -- are worth a collective $172 billion. The ultra high net worth alumni from MIT, based in Cambridge, Mass., have the highest average net worth of $257 million.
|Yale University; Private|
Yale can boast of graduates like Meryl Streep and five U.S. presidents as well as having the eighth highest number of ultra high net worth alumni. The 568 wealthiest alumni from Yale, based in New Haven, Conn., are worth a collective $125 billion.
|Cornell University; Private|
In Ithaca, N.Y., Cornell's 528 wealthiest alumni are worth a combined $60 billion.
|Princeton University, Private|
The wealthiest alumni from Princeton University in Princeton, N.J. are worth a collective $70 billion.
|University of Virginia; Public|
The highest-ranked public university in the list is UVA, based in Charlottesville, Va. Its wealthiest alumni are worth a total of $31 billion. UVA has the highest percentage of self-made ultra high net worth individuals. Notable alumni include talk show host Katie Couric and comedian and writer Tina Fey.
|Boston University; Private|
Boston University's 491 wealthiest individuals are worth a combined $38 billion. The university's notable alumni include radio personality Howard Stern and actresses Marisa Tomei and Julianne Moore.
|Northwestern University; Private|
Northwestern's 451 wealthiest alumni are worth a total of $46 billion. Based in Evanston, Ill., Northwestern's famous Wildcats include a slew of actors like Warren Beatty, plus Chicago Bulls and White Sox owner Jerry Reinsdorf.
|University of California, Berkeley; Public|
Formerly a liberal stalwart of the hippie generation, today Cal is known for its engineering and business programs. Its wealthiest 447 alumni are worth a combined $72 billion.
|University of Michigan; Public|
The University of Michigan's 410 richest alumni are worth a collective $70 billion.