ROME (REUTERS).- The Italian edition of Rolling Stone has named Prime Minister Silvio Berlusconi its "rock star of the year," paying tribute to his "lifestyle worthy of the greatest rock star."

An illustration of a smiling Berlusconi, who weathered a summer of scandals over his relations with an 18-year-old underwear model and allegations he slept with a prostitute after a party, emblazons the cover of the Rolling Stone's December issue, against the backdrop of the Italian flag.

Carlo Antonelli, editor of Rolling Stone Italy, said the 73-year-old media mogul had been chosen unanimously by the magazine's editorial staff.

"This year the choice was unanimous, for his obvious merits due to a lifestyle for which the words 'rock and roll' fall short," Antonelli said in a statement.

"Rod Stewart, Brian Jones, Keith Richards in their prime were schoolboys compared to him."

It has been a turbulent year for billionaire Berlusconi, with his second wife Veronica Lario demanding a divorce in May after photographs emerged of Berlusconi attending the 18th birthday party of aspiring model Noemi Letizia.

Berlusconi, who had told his wife he going to a conference, has denied any "steamy affair."

Italy was subsequently convulsed, with the Italian church voicing its "mortification," when call girl Patrizia D'Addario in July alleged she had been paid to attend a party at Berlusconi's Rome mansion and had slept with the prime minister.

She even produced recordings of conversations with a man she said was Berlusconi. The prime minister has not directly commented but has publicly acknowledged he is "no saint."

In a book due to be published on Tuesday, entitled "Take Your Pleasure, Prime Minister', D'Addario recounts an evening at Berlusconi's residence where he was surrounded by around 20 young women, many of whom seemed to know him well.

The scandals made front page news around the globe, but had only a moderate impact on Berlusconi's robust popularity ratings in Italy. Antonelli denied that his magazine had any political agenda behind its choice.

"We are far from favoring left or right ... Silvio Berlusconi's daily behavior, his furious vitality, his inimitable lifestyle have given him, especially this year, incredible international popularity," he said.

(Reporting by Daniel Flynn, editing by Paul Casciato)