If you think Apple’s iPads are expensive, consider the price of the company’s stock.

Shares of the Cupertino, Calif., gadget giant yesterday neared the $600 mark — almost $100 higher than the price of the brand-new iPad slated for release tomorrow — giving the company a market value of nearly $550 billion.

Stock in Apple — which has seen a surge in pre-orders for the new iPad, which features a higher-resolution screen and the option to surf the Internet at faster speeds — surged as high as $594.73 before closing up $21.48, or 3.8 percent, at $589.58.

Two analysts hiked their forecasts for sales and earnings, saying they expect Apple shares to pass $700 within the next 12 months.

“Investors still underestimate the potential earnings upside at Apple,” Morgan Stanley analyst Katy Huberty wrote in a note to clients, predicting Apple will earn $50 a share this year on feverish demand for iPhones and iPads.