The world's billionaires are holding more than $1.7 trillion in cash — the highest amount since one firm began recording the measure in 2010.

Because of what they perceive to be growing risks in the economy and world, the world's 2,473 billionaires are keeping 22.2 percent of their total net worth in cash, according to the Wealth-X Billionaire Census.

The group has also benefited from the recent surge in so-called liquidity events from corporate acquisitions and mergers. Altogether, their cash hoard is now roughly the size of the Brazil's GDP.

"Billionaires are taking money off the table where available, while uncertainties in the economy and the historical highs found in deals have resulted in cash-flush portfolios," the report said.



The firm's findings are in line with those from other recent surveys. A study released by UBS last month said wealthy Americans are keeping around 20 percent of their portfolios in cash, in line with their post-2008 average. More are considering reducing their exposure to the markets because of uncertainty over the presidential election, UBS said.