Noah was on the ark for approximately 370 days, assuming a lunar calendar of 360 days. Noah first entered the ark on day 17 of the second month and left the ark on day 27 of the second month the following year.
Noah was 500 years old when he was first mentioned in the Bible and 600 years old when he entered the ark. Although it is not specifically mentioned, it took him almost 100 years to complete the ark. There were eight people on the ark altogether: Noah, his wife, Noah's three sons (Shem, Japheth and Ham), and their wives.