Genesis 25:5-8

Now Abraham gave everything that he had to Isaac; but to the sons of his concubines [Hagar and Keturah], Abraham gave gifts while he was still living and he sent them to the east country, away from Isaac his son [of promise]. The days of Abraham’s life were a hundred and seventy-five years. Then Abraham breathed his last and he died at a good old age, an old man who was satisfied [with life]; and he was gathered to his people [who had preceded him in death]. [Gen 15:15; Heb 11:13-16]