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.

Anti-nuclear activists demonstrate during a “Say to Goodbye to Nuclear Energy” protest on September 11, 2011 in Kobe, Japan. Japan is marking sixth months since a magnitude 9.0 earthquake struck Japan offshore on March 11 at 2:46pm local time, triggering a tsunami wave of up to ten metres which engulfed large parts of north-eastern Japan and also damaged the Fukushima nuclear plant, causing the worst nuclear crisis in decades. The current number of dead and missing is reportedly estimated to be 22,900. (Photo by Buddhika Weerasinghe/Getty Images)

A recently rescued grey seal pup looks up from its indoor kennel at the RSPCA West Hatch Wildlife Centre on January 9, 2012 in Taunton, England. The centre is currently dealing with a number of mainly grey seals that have been rescued from the coast due to the recent storms. Staff at the centre hope to release all the seals back into the wild by the spring. (Photo by Matt Cardy/Getty Images)

People, carry food and water, past a tractor stuck in mud, stones and debris that were piled in a flood in the mountain village of Sipkovica, just above the town of Tetovo, in northwestern Macedonia, on Tuesday, August 4, 2015. A small number of people including children have died in floods that erupted after an hour of heavy torrential rains and strong winds that hit Tetovo and northwestern region of Macedonia late on Monday. (Photo by Zoran Andonov/AP Photo)

The annual Sculpture by the Sea exhibition in Sydney features dozens of sculptures on Bondi and Tamarama beaches and along the coastal path between them. The free outdoor exhibition, now in its 18th year, stretches for 2km along the coastline and includes work by artists from 16 countries. It runs from 23 October to 9 November 2014. Here: “Breaching” by Michael Greve is displayed during the 2014 Sculptures by the Sea exhibition at Marks Park on October 23, 2014 in Sydney, Australia. (Photo by Cameron Spencer/Getty Images)

Mikhail Kalashnikov, the father of the world's most popular assault rifle, is handed an AK-74 November 23, 2002 in Izhevsk,1000 East km. from Moscow. November 23 marked the 55th anniversary of the release of the first Kalashnikov gun. According to the Moscow-based Center for Analysis of Strategic and Technologies some 70 million to 100 million Kalashnikovs have been built worldwide since 1947, compared about 7 million to Kalashnikov's Western rival the M-16 assault rifles. (Photo by Oleg Nikishin/Getty Images)

One-year-old female giant panda cub Nuan Nuan reacts inside her enclosure during joint birthday celebrations for the panda and its ten-year-old mother Liang Liang at the National Zoo in Kuala Lumpur on August 23, 2016. Giant pandas Liang Liang, aged 10, and her Malaysian-born cub Nuan Nuan, 1, were born on August 23, 2006 and August 18, 2015 respectivetly. (Photo by Mohd Rasfan/AFP Photo)

Two people ride a motorcycle as a Taiwanese Air Force Mirage 2000 fighter jet approaches for landing at an air force base in Hsinchu in northern Taiwan on May 23, 2024. China on May 23 encircled Taiwan with naval vessels and military aircraft in war games aimed at punishing the self-ruled island after its new president vowed to defend democracy. (Photo by Yasuyoshi Chiba/AFP Photo)