Assuming a 6% rate on those funds, this would generate 8.22 billion in interest income. Divide that by 939.06 million shares outstanding, and that comes out to new earnings of 8.75 per share. Reduce that number by the company's current effective tax rate of 26% and you come up with 6.48 per share. Add that to the current per share earnings of 44.11 and it results in 50.59 of earnings per share.
Remember, no additional growth of earnings due to higher revenues have been factored in. You take the 50.59 earnings per share, multiply it times the current price to earnings ratio of 10.62 and you get a price of 537.24 per share.
Disclosure: Author owns AAPL.