241543903 (a.k.a “Heads in Freezers”) is a numerical keyword associated with a photo meme that involves people taking pictures with their heads in the freezer & sharing them online. By tagging a series of image files with a cryptic number, a high level of search engine optimization can be easily achieved. As a result, typing “241543903” into image search engines like Google Images successfully yields pages after pages of pictures showing people’s heads in freezers.
In 2009, David Horvitz started the “Heads in Freezers” meme. Participants took photos of their heads in freezers, tagged them with “241543903” and uploaded them to social media sites like Tumblr.

Kevin and Merith Starren have their picture taken by Merith's brother Mark Ernst (R) and nephew Logan Ernst (L) in front of a 50-foot snowman named “Granddaddy” in Gilman, Minnesota, March 6, 2014. (Photo by Eric Miller/Reuters)

Figure Skating, ISU World Figure Skating Championships, Ladies Short Program, Boston, Massachusetts, United States on March 31, 2016: Ashley Wagner of the United States stumbles and falls while celebrating after competing. (Photo by Brian Snyder/Reuters)

An a music therapist plays harp during treatment of patients suffering from the coronavirus disease (COVID-19) in the Intensive Care Unit (ICU) at Havelhoehe community hospital in Berlin, Germany, December 6, 2021. (Photo by Fabrizio Bensch/Reuters)

Two helicopters are seen following a collision near Seaworld, on the Gold Coast, Australia, 02 January 2023. Four people are dead and another 13 injured after two helicopters collided before one crashed into the Broadwater on the Gold Coast. (Photo by Dave Hunt/EPA/EFE/Rex Features/Shutterstock)

Desiree Urban is painted at Columbus Circle as body-painting artists gathered to decorate nude models as part of an event featuring artist Andy Golub, Saturday, July 26, 2014, in New York. Golub says New York was the only city in the country that would allow his inaugural Bodypainting Day. (Photo by John Minchillo/AP Photo)

A woman dressed in a dirndl, a kind of traditional Bavarian clothing, jumps into Lake Schlier on July 30, 2006 in Schliersee, Germany. The event called "Dirndlfliegen" ("Dirndl Flying") was sponsored by a local fashion store and a big Austrian Dirndl manufacturer. While these kind of events had been held in Austria before, this was the first of its kind in Germany. 29 women and one man wearing a wig participated in the event that held a new Dirndl as the grand prize. (Photo by Andreas Leder/Getty Images)