Updated from 11:19 a.m. EST to provide information about $500 share price in the third paragraph.NEW YORK ( TheStreet) -- Apple ( AAPL) got "iCahned" Tuesday, as the billionaire investor said he believes Apple shares are "extremely undervalued" and the company needs to execute a larger buyback. Raising it again in a relatively short period of time would be short-sighted, and that's not what Apple needs right now. Icahn advocating for a larger buyback at this vantage point doesn't make sense especially because Apple just raised its buyback to $60 billion from $10 billion a few months ago. I guess $60 billion isn't enough. Nonetheless, Apple shares climbed over $500 Tuesday on continued optimism over Icahn's tweets, reaching a high of $504.25, before finally settling at $498.50. It was the first time Apple shares had reached $500 since January, despite the market rallying throughout 2013. It's possible Apple shares rise in the short-term, as investors place optimism that Icahn can agitate Apple enough to get it to do something. That optimism is short-sighted, as the focus for Apple over the next 12 months should be focusing on products, software and services that can help in the long run, not just buying back additional shares. When Apple reported its fiscal second-quarter earnings, it raised its buyback program to $60 billion, tacking on $50 billion to the largest corporate buyback in U.S. history. The iPad maker also raised its quarterly dividend by 15% to $3.05 per share, bringing its total cash return to shareholders over the next three years to $100 billion. Apple needs some cash to run its operations and fund R&D. Putting a majority of it now to fund a bigger buyback would be the short-term nature of Wall Street vs. the long-term thinking of Apple and tech in general. It's a culture clash, and one I'm not sure Mr. Icahn is likely to win, at least for now. The company sold $17 billion in debt earlier this year in part to alleviate the issue of its massive international cash hoard. In an interview with The Wall Street Journal, Icahn said Apple is worth $625 per share, even with little to no earnings growth, arguing that the the Cupertino, Calif.-based tech giant can borrow more money to fund an expanded buyback program. What Icahn is advocating is for the company to pile on even more debt onto its balance sheet to help fund the buyback. Apple had $146.5 billion in cash and equivalents at the end of its fiscal third-quarter, but that number is likely to come down, albeit slightly, as the company returns $100 billion in cash to shareholders over the next few years. Much of Apple's cash is international, which has been the issue before with doing larger buybacks and dividends. David Einhorn suggested using preferred stock, in an attempt to alleviate this issue, by trying not to repatriate the off shore cash. Barclays Capital analyst Ben Reitzes, who rates shares "overweight," with a $525 price target, noted it could be possible that Icahn has a plan for the overseas cash. "As a result, it could also be possible that Mr. Icahn has suggestions for a faster plan and even has plans for overseas cash that are not yet evident to investors," Reitzes penned in his note.