Little Caesars Pizza's commercial for its "hot and ready" pretzel crust pizza was the most memorable ad among millennials in September, according to a ranking from Nielsen.

The company's Nielsen Brand Effect ranks the top 10 ads among the demographic, asking a sample of viewers whether they remember ads, the brand of the ad, whether they liked the spot and whether it impacted their intent to purchase the product.

Compared to the average ad, Little Caesars' spot was 2.59 times more likely to be remembered and associated with the correct brand among millennials, defined here as viewers between 18 and 33 years old, according to Nielsen.

Other memorable ads among the demographic during the month include Snickers' "Johnny JamBoogie Aerobics," Old Navy's "Court Order for Pants" starring Amy Poehler and McDonald's "Tailgating: Chicken McNuggets."

Party City's "Marvel Costume Party" was No. 1 among the broader 18-to-49 demographic, by comparison, with Werther's Candies "Inside Candy Store" at No. 2 and USAA United Services Automobile Association's "Thank You-Military Families" coming in third, according to Nielsen. Four ads appear in the top 10 among both millennials and adults up through 50: Party City, Buick Motors, Old Navy and Red Lobster.

Here's a look at the top 10 ads that struck a chord with millennials in September.