The phrase "accumulated enormous" is correct and usable in written English.
It can be used when describing a large amount of something that has been gathered or built up over time.
Example: "The company has accumulated enormous wealth through its successful investments."
Alternatives: "gathered significant" or "amassed substantial".
As a result, it has accumulated enormous foreign exchange reserves that reached $224.8 billion last month.
Along with spectacular wealth, he accumulated enormous political influence, becoming a close ally of Mr. Yeltsin's.
He still does very well, and in the final 20 years the family has accumulated enormous wealth, but the soil has gone.
He also accumulated enormous good will for his compassionate, stabilizing behavior after 96 Liverpool fans died in a stadium crush known as the Hillsborough disaster.
In 1994, Mr. Lamy left Brussels and returned to Paris to help in trying to salvage Credit Lyonnais, a troubled big bank that had accumulated enormous debts and required repeated taxpayer bailouts.
He relied on present and former military and security men, who accumulated enormous political and economic power and have done little to integrate the northern Caucasus more closely into Russia.
It has also caused them to accumulate enormous foreign exchange reserves through currency market intervention.
They received personal credit for nearly every improvement at their companies, accumulating enormous wealth and prestige in the process.
They can accumulate enormous stakes in companies without tipping their hand and driving up the share price.
The tech and finance booms have allowed individuals to accumulate enormous sums of money at a startlingly young age.
"We're in an unsustainable situation in terms of accumulating enormous deficits," said Clyde Prestowitz, a former trade negotiator in the Reagan administration, and now president of the Economic Strategy Institute.
