Apple may have sold more that 500,000 iPad 2 devices after retail outlets ran out of the tablet device on its debut weekend.

Stores run by Apple, Target Corp. nd Best Buy have already sold out of the device, while online orders via Apple's website are taking up to a month for delivery.

Apple sold more than 300,000 units of the first iPad in the 24 hours after its April debut.

Apple's new iPad model comes in white and black, is lighter, thinner, includes a more powerful processor and has front and rear cameras. It ranges in price from $499 for a base model to $829 for the top-of-the-line version.

Materials used in the 33GB version of the iPad 2 cost about $326.60, according to research firm IHS ISuppli. That?s up from $320 for the earlier model.