We had sent Noah to his people, so he stayed with them one thousand years less fifty calendar years. Then the flood took them while they were wicked.
Translation endnotes
[29:14] Until God revealed the secret code prophesied in chapter 74, we did not have a satisfactory answer to the question, why "one thousand minus fifty instead of the conventional expression, nine hundred and fifty?" Every element of the Quran, its chapters, verses, words, and letters, including its numbers, plays a role in the mathematical structure of the Quran. For instance, the sum of all the different numbers in the Quran without repetition gives us 162146 (19x8534). If the expression in the verse was "nine hundred and fifty," then the sum would be 900 extra and would not participate in the numerical system based on code 19. Furthermore, the age of Noah being a multiple of 19 also supports this relationship. It seems too difficult to accept such a long lifespan for a human being. Since, the Quran contains its own scientific authentication, we have no choice but to trust this apparently incredible information. The Bible too gives 950 as Noah's age (Genesis 9:29). Chapter eleven of Genesis mentions nine names who lived more than a hundred years, such as Shem (600), Arphaxad (438), Salah (433), Eber (464), Peleg (239), Reu (239), Serug (230), Terah (205),