I have read that Adi Shankaracharya's parents were childless for many years and they worshipped Lord Shiva, so that they will be blessed with a son. Then the Lord appeared in their dream and asked them "You can choose to have either one extraordinary son with a short life or many ordinary sons".
They chose the extraordinary son.
It is said that Adi Shankaracharya left his house at the age of 12 and became a sanyasi. I want to know after that how long he lived.
Quoting from here ,
Shankara’s dates
Modern scholarship is agreed on dates in the 8th century C.E., though it has proved impossible to reach agreement on Shankara’s precise dates of birth or death. Some religious groups, however, ascribe B.C.E. dates to him. If these dates were true, then much of what is claimed about his activities, especially his debates with Buddhists and Jains, is thrown into doubt.
Of the major Shankara Mathams active today, the Kanchi, Dwaraka, and Puri ascribe the dates 509–477 B.C.E. to Shankara. The Sringeri Peetham, on the other hand, accepts the 788–820 C.E. dates.
.....Even though he lived for only thirty-two years, his impact on India and on Hinduism cannot be stressed enough, as he countered the increasing sacerdotalism (the belief that priests can mediate between humans and god) of the masses, and reintroduced a purer form of Vedic thought.
According to wiki too he died at the age of 32.
So,20 years more will be the answer to your question.
