* Futures up: Dow 40 pts, S&P 4 pts, Nasdaq 31.25 pts
By Yashaswini Swamynathan
July 27 (Reuters) - U.S. stock index futures were higher on Wednesday, helped by Apple's stellar results, and ahead of the Federal Reserve's comments on interest rates.
* Apple shares soared more than 6 percent to $102.66 in premarket trading after the company sold more iPhones than expected in the third-quarter and gave an upbeat current-quarter forecast.
* Investors are also waiting to hear what the Federal Open Market Committee (FOMC) has to say about raising interest rates and the health of the U.S. economy.
* The FOMC has little room to raise rates this time, but a recent set of strong economic data can strengthen the case for an increase earlier than the market anticipates.
* The committee will end its two-day meeting with a statement at 2:00 p.m. ET (1800 GMT).
* Traders have priced in a 19.5 percent chance of a rate increase in September and a 42.8 percent chance in December, according to CME Group's FedWatch tool.
* Global stocks got a boost after Japan Prime Minister Shinzo Abe unveiled a $265 billion stimulus package to reflate the country's economy.
* Of the 157 S&P 500 companies that have reported results so far, 69 percent have topped earnings estimates. In a typical quarter, 63 percent of companies beat expectations, according to Thomson Reuters data.
* Facebook, Amgen and Whole Foods are some of the companies that are expected to report after the bell on Wednesday.
* Analog Devices shares jumped 9.5 percent to $68.81 after the company struck a deal to buy Linear Technology for $14.8 billion. Linear's stock was down 1.2 percent at $61.75.
* Twitter plunged 11 percent after the microblogging service provider reported its slowest quarterly revenue growth since going public in 2013.
Futures snapshot at 6:57 a.m. ET:
* Dow e-minis were up 40 points, or 0.22 percent, with 23,468 contracts changing hands.
* S&P 500 e-minis were up 4 points, or 0.18 percent, with 117,013 contracts traded.
* Nasdaq 100 e-minis were up 31.25 points, or 0.67 percent, on volume of 19,191 contracts. (Reporting by Yashaswini Swamynathan in Bengaluru; Editing by Anil D'Silva)