Federal authorities yesterday charged a Queens man with engineering a $50 million real-estate scam and pocketing cash from “risk-free deals.”

FBI agents arrested 29-year-old Gershon Barkany, of Far Rockaway, after he cheated investors out of money they gave him to flip properties, officials said.

Prosecutors said one victim invested $46.5 million after Barkany shared a plan to purchase a Manhattan office building, an Atlantic City hotel and properties in Queens and The Bronx.

“The defendant admitted that there were no deals and that all the documents that he had provided to the investor were false,” US Attorney Christopher Caffarone wrote in court papers.