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.

This is a portion of the first color 360-degree panorama from NASA's Curiosity rover, made up of thumbnails, which are small copies of higher-resolution images. The mission's destination, a mountain at the center of Gale Crater called Mount Sharp, can be seen in the distance, to the left, beginning to rise up. The mountain's summit will be imaged later. (Photo by NASA/JPL-Caltech/MSSS)

This is the mesmerising image of a colourful Milky Way shining down on Mount Fuji. Steve Lance Lee, 37, captured the sky above the iconic mountain whilst on his honey moon in Lake Kawaguchiko, Japan. Mount Fuji is illuminated underneath the galaxy of stars, creating an impressive landscape. Here: The beautiful image captured by Steve Lance Lee of the Milky Way seemingly errupting from Mt. Fuji in Japan. (Photo by Steve Lance Lee/Caters News)

These images give a rare insight into the life of a 19th Century Indian Maharajah. Maharajah Ram Singh ruled in the famous pink city of Jaipur between 1835 and 1880, and was also a keen photographer. Here: Full portrait of a woman in the harem in the royal palace of Jaipur, India, 1857 – 1865. (Photo by Maharaja Ram Singh III/Alinari via Getty Images)

These stunning images show a group of aerial artists lighting up the night sky. Taken by photographer Casey Grimley, 37, the photos show pole dancers and aerial artists at various locations in Southern California, including the famed Joshua Tree National Park. (Photo by Casey Grimley/Caters News Agency)

In this composite image (top) flooding is seen in the Toowoomba central business district on January 10, 2011 and (bottom) the same location as seen on January 5, 2012 in Toowoomba, Australia. January 10 marks the one year anniversary of the inland tsunami that devestated southern Queensland's Lockyer valley killing 23 people. (Photos by Dan Proud (top) and Lisa Maree Williams (bottom) /Getty Images)

In this handout image provided by Sydney Tower Eye, a visitor scans the skyline and harbour of Sydney from a viewing platform at the Sydney Tower Eye, on December 16, 2011 in Sydney, Australia. Sydney is suffering from its coldest start to summer since 1960. (Photo by Eugene Tan/Hausmann Communications via Getty Images)

In this handout image provided by Carnival Australia, captain of the Queen Mary 2 Christopher Rynd poses on the desk of the Queen Mary 2 on February 8, 2012 in Perth, Australia. (Photo by James Morgan/Carnival Australia via Getty Images)