Dalton Chiscolm is unhappy about the customer service at his bank - really, really unhappy.

In August, Mr Chiscolm sued Bank of America, the largest US bank and its board, demanding that "$US1,784 billion, trillion" be deposited into his account the next day.

He also demanded an additional $US200,164,000, court papers show.

Attempts to reach Mr Chiscolm were unsuccessful and a Bank of America spokesman declined to comment.

"Incomprehensible," US District Judge Denny Chin said in a brief order released in Manhattan federal court.

"He seems to be complaining that he placed a series of calls to the bank in New York and received inconsistent information from a 'Spanish woman,'" the judge wrote.

"He apparently alleges that cheques have been rejected because of incomplete routing numbers."

Judge Chin has experience with big numbers.

He is the judge who sentenced Bernard Madoff to a 150-year prison sentence for what the government called a $US65 billion Ponzi scheme.

Bank of America Corp faces real legal problems, including New York Attorney-General Andrew Cuomo's threat to sue its chief executive and a judge's embarrassing rejection of a settlement with the US Securities and Exchange Commission.

Yet the money Mr Chiscolm wants could dwarf all the bank's other problems.

It is larger than a sextillion dollars, or a 1 followed by 21 zeros. Mr Chiscolm's request is equivalent 1 followed by 22 digits.

The sum also dwarfs the world's 2008 gross domestic product of $US60 trillion, as estimated by the World Bank.

"These are the kind of numbers you deal with only on a cosmic scale," said Sylvain Cappell, New York University's Silver Professor at the Courant Institute for Mathematical Sciences.

"If he thinks Bank of America has branches on every planet in the cosmos, then it might start to make some sense."

Judge Chin gave Mr Chiscolm until October 23 to better explain the basis for his claims, or else see his complaint dismissed.

- Reuters