Lehman Brothers Holding Inc has agreed to sell apartment owner Archstone to rivals Equity Residential and AvlanonBay Communities Inc for $6.5 billion in cash and stock, Lehman said on Monday.

Lehman and its affiliate, Lehman Commercial Paper Inc, will receive $2.685 billion in cash, as well as about 34.5 million shares of Equity Residential stock and 14.9 million shares of AvalonBay. Based on Friday's closing price, the shares have a value of $3.8 billion.

Lehman Brothers will own 9.8 percent of Equity Residential and 13.2 percent of AvalonBay.

The purchasers have up to 120 days to close the transaction, which is not subject to approval by shareholders of Equity Residential or AvalonBay.

(Reporting by Ilaina Jonas; Editing by Gary Hill)