NEW YORK — President Barack Obama’s visit has set a standard for “The View.”

Obama’s appearance with a convalescing Barbara Walters and her co-hosts reached 6.6 million viewers last week, the biggest audience ever for a show that’s been on the air since 1997, the Nielsen Co. said.

It was believed to be the first time a sitting president has visited a daytime talk show. Obama was indirectly responsible for the previous record for “The View,” when 6.2 million people watched the day after he was elected president in 2008.

“’The View’ has proven to be an important stop for political candidates and is appointment television for our loyal audience who value our opposing views,” said Walters, who came in during her recuperation from heart surgery to appear with the president.

Obama reached more people on “The View” than he ever has on the Sunday morning political talk shows “Meet the Press,” ‘’Face the Nation” and “This Week,” Nielsen said.

Nickelodeon’s “iCarly” had a big night Friday, with 7.7 million people watching a special episode that offered a glimpse of the lead character’s room for the first time, Nielsen said. That was a bigger audience than all but seven shows on prime-time broadcast television last week.

It was another slow summertime week for broadcasters, which couldn’t muster 10 million viewers for any program. NBC’s “America’s Got Talent” led the way.

CBS won the week in prime time by a comfortable margin, averaging 6 million viewers (3.9 rating, 7 share). ABC had 4.9 million viewers (3.1, 6) and NBC had 4.7 million (2.9, 5). Despite being in fourth among all viewers with a 4.5 million average (2.7, 5), Fox won among the valuable 18-to-49-year-old demographic. ION Television had 1.2 million (0.8, 1) and the CW had 950,000 (0.6, 1).

Among the Spanish-language networks, Univision led with a 3.4 million average (1.7, 3), Telemundo had 960,000 (0.6, 1), TeleFutura had 680,000 (0.3, 1), Azteca had 190,000 and Estrella had 170,000 (both 0.1, 0).

NBC’s “Nightly News” topped the evening newscasts with an average of 7.4 million viewers (4.9, 11). ABC’s “World News” was second with 6.7 million (4.6, 10) and the “CBS Evening News” had 5 million viewers (3.4, 7).

A ratings point represents 1,149,000 households, or 1 percent of the nation’s estimated 114.9 million TV homes. The share is the percentage of in-use televisions tuned to a given show.

For the week of July 26-August 1, the top 10 shows, their networks and viewerships: “America’s Got Talent” (Wednesday), NBC, 9.76 million; “NCIS,” CBS, 9.73 million; “America’s Got Talent” (Tuesday), NBC, 9.69 million; “The Bachelorette,” ABC, 8.87 million; “Two and a Half Men,” CBS, 8.4 million; “The Big Bang Theory,” CBS, 8.32 million; “60 Minutes,” CBS, 7.95 million; “The Mentalist,” CBS, 7.43 million; “NCIS: Los Angeles,” CBS, 7.21 million; “Big Brother 12” (Sunday), CBS, 7.11 million.