(Reuters) - The online health insurance exchanges at the heart of President Barack Obama's healthcare law opened for business on October 1, although technical glitches stalled the launch in many states.

Here are some first day statistics reported by the exchanges, states and the federal government:

* About 2.8 million people visited healthcare.gov - the main website for the 36 state exchanges being run by the federal government - between midnight and mid-afternoon, theU.S. Department of Health and Human Services said.

* NY State of Health, New York state's exchange, reported 7.5 million website visits by mid-afternoon.

* Kentucky's exchange, kynect, saw 57,625 unique visitors from its midnight launch until 2:30 p.m., according to the Kentucky governor's office. Nearly 2,000 applications had been started, with 1,235 completed. The kynect contact center fielded 3,243 calls and 110 e-mails. The average visitor stayed on the site for 11 minutes.

* Access Health CT, Connecticut's exchange, reported 28,280 unique visitors as of 4 p.m. It processed 167 applications, 83 of which were for subsidized purchases of commercial insurance products, while 84 were for Medicaid coverage. The call center received 1,930 calls during the day, with the average call time trending at about 9 minutes.

* Nevada Health Link reported 2,179 accounts created through its exchange as of 1 p.m. local time, and 1,111 phone calls received.

* Arkansas's Health Insurance Marketplace website, arhealthconnector.org, had registered 15,934 hits from midnight to 3 p.m., according to the Arkansas governor's office.

* The Connect for Health Colorado Marketplace said it had over 34,500 unique visitors and more than 1,300 accounts created in the first three hours.

* Illinois' exchange, Get Covered Illinois, reported 65,043 unique visitors as of 3:30 p.m. CST after opening at midnight. The state received more than 1,100 online applications, while the help desk received more than 350 calls.

(Reporting by Lewis Krauskopf and Sharon Begley)