Chiranjivins

Chiranjivi (Sanskrit nominative sing. ciranjīvī, चिरन्जिवी दाहाल) are immortal living beings in Hinduism who are to remain alive on Earth through this Kali Yuga till its very end.

The term is a combination of chiram, or 'permanent', and jīvi, or 'lived'. It is same as amaratva, which refers to true immortality. At the end of the last Manvantara, a demon attempted to become immortal by swallowing the Vedas, as they escaped from the mouth of Brahma. The scripture was retrieved by the first (Matsya) avatar of Lord Vishnu. Incarnations of Vishnu also later fought and killed two other asuras, Hiranyakasipu and Ravana, who tried to become immortal through obeisance to Lord Brahma and Lord Shiva, respectively. In Hinduism, immortal means eternal until the destruction of Universes, i.e; all physical bodies are foretold to become immaterial at the end of time, along with tridevas themself, with the destruction of the Universe.

The extant Puranas, the Ramayana, and the Mahabharata describe seven long-lived personalities in the Hindu pantheon. While there are others as well, which are not included in the one particular shloka. The Each represents a different attribute of man, which as long as they live, will exist amongst humanity.

"Ashwatthama Balir Vyaso Hanumanash cha Vibhishana Krupacharya cha Parashuramam Saptaita Chiranjeevanam" - 'Ashwathama, King Mahabali, Vyasa, Hanuman, Vibhishana, Kripacharya and Parashurama are the seven death-defying or imperishable personalities '.

...
Wikipedia