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.

Revellers use water guns as they participate in a water fight during Songkran Festival celebrations at Kowloon City district, known as Little Thailand as there is large number of restaurants and shops run by Thais, in Hong Kong April 12, 2015. The Songkran festival, also known as the water festival, marks the start of Thailand's traditional New Year and is believed to wash away bad luck. (Photo by Tyrone Siu/Reuters)

A participant wearing a motorcycle helmet gets sprayed with firecrackers, during the “Beehive Firecrackers” festival at the Yanshui district in Tainan, Taiwan on March 1, 2018. According to Taiwan's Tourism Bureau, the “beehive” festival started in the late 1885 as a request to the gods to spare Yanshui from a cholera outbreak which was making its way through the villages. (Photo by Tyrone Siu/Reuters)

Kourtney Roy makes eerie self-portraits in desolate yet dramatic locations – with wigs and wardrobe straight out of 1950s melodrama. In these shots, from her “Enter as Fiction – California” series, she plays characters caught in desolate, often abandoned settings. (Photo by Kourtney Roy/Galerie Catherine et André Hug/The Guardian)

A reveller reacts during a water fight at Songkran Festival celebrations in Bangkok April 13, 2016. The three-day Songkran Festival starts on 13-15 April annually and is celebrated with splashing water and putting powder on each others faces as a symbolic sign of cleansing and washing away the sins from the old year. (Photo by Jorge Silva/Reuters)

“David Doubilet (born 28 November 1946) is a well known underwater photographer known primarily for his work published in National Geographic Magazine. He was born in New York and started taking photos underwater at the young age of 12. He started with a Brownie Hawkeye in a rubber anesthesiologist's bag to keep the water out of the camera. During his summer holidays, he spent his time along the New Jersey coast. He later worked as a diver and photographer for the Sandy Hook Marine Laboratories in New Jersey. He also spent much time in the Caribbean. While a dive instructor in the Bahamas he found his motivation to capture the beauty of the sea and everything in it”. – Wikipedia. (Photo by David Doubilet/National Geographic)

A demonstrator holds up a picture depicting Russian President Vladimir Putin with make-up, during a protest by the gay community in Amsterdam April 8, 2013. Russia does not discriminate against homosexuals, Putin told reporters in Amsterdam on Monday where he was greeted by gay rights and other activists critical of Russia's track record. Putin is on one-day visit in the Netherlands for the start of the Netherlands-Russia Year. (Photo by Cris Toala Olivares/Reuters)

A undated handout image provided by the Bochum University of Applied Sciences (Hochschule Bochum) on 04 October 2013 shows the German team Bochum's Cruiser class solar car during a test drive in the Northern Territoty, Australia, 16 September 2013. The Dutch vehicle is competing in the World Solar Challenge, driving from Darwin to Adelaide starting on 06 October 2013. (Photo by Hochschule Bochum/EPA)