Sony Pictures' controversial movie, The Interview, has done well in its unconventional release, having been rented or purchased online and through cable, satellite and telecom providers more than 4.3 million times.

Sony Pictures said the Seth Rogen-James Franco comedy generated more than $31m (£20m, €26m) from online, cable and telecom sales since its December release. The movie "is Sony Pictures' #1 online film of all time," according to the studio.

That is much higher than the $5m revenues the film earned from its theatrical release until date. Sony Pictures released the movie via 580 independent theatres, as large theatre chains declined to exhibit the movie.

The film is estimated to have cost about $75m to produce and market.

"We released 'The Interview' through a variety of platforms, and we continue to look for other distribution options," Michael Lynton, Sony Pictures' chairman and chief executive, said in an email to staff.

"Our studio takes great pride in continuing to grow the release of this movie and making it a success."

The studio earlier said the film made $18m (£11.5m) worldwide in its first four days of release. Of the $18 million made, just over $15m (£9.6m) has come from downloads. The film was made available to download on prominent online platforms such as iTunes, Xbox, YouTube and Google Play.

The comedy, which depicts the attempted assassination of North Korean leader Kim Jung-un, has been at the centre of a controversy involving a cyber-attack on Sony Pictures, threats of terrorism and the brief cancellation of the film's release.

Sony decided to cancel the film's release after five of the US's biggest cinema chains elected not to show the film after bomb threats were made against theatres showing it. However, this was reversed just prior to Christmas, when Sony announced plans to release it online and in cinemas willing to screen the movie.

The original cyber-attack targeting Sony saw a number of private emails leaked, giving the world some insight into the inner workings of the studio. Those leaks have since stopped following Sony's original cancellation and the intervention of the US government.

President Barack Obama criticised Sony for cancelling the film as the FBI announced that North Korea were involved with the cyber-terrorism attack.