In "One Day in the Life of Ivan Denisovich" how long was the prison sentence that Ivan Denisovich was serving?

Aleksandr Solzhenitsyn's short novel "One Day..." turned out to have a huge influence on the Soviet Union. It is a sparse, tersely written, downbeat narrative of a single day of the labour-camp imprisonment of a fictitious Soviet prisoner; never before had an account of Stalinist repressions been openly distributed and it is perhaps the most powerful indictment of the Soviet Gulag ever written.

Solzhenitsyn had had first-hand experience in the Gulag system. He was imprisoned from 1945 to 1953 for writing derogatory comments in letters to friends about the conduct of the war by Joseph Stalin, whom he referred to by epithets such as "the master" and "the boss"

In the story Ivan Denisovich Shukhov has been sentenced to a camp in the Soviet Gulag system. He was accused of becoming a spy after being captured briefly by the Germans as a prisoner of war during World War II. Although innocent, he is sentenced to ten years in a forced labour camp. The novel recounts the hardship, the petty vindictiveness of the guards and, above all, the mind-numbing tedium of everyday life.

It is, perhaps, well summarised by Shukhov’s reflections at the end of what has been quite a fulfilling work-day for once:

“There were three thousand six hundred and fifty-three days like that in his stretch. From the first clang of the rail to the last clang of the rail.

“The extra three days were for leap years.”