Genesis 50:3

And while they were fulfilling his orders, forty days passed. For this was the method of embalming dead bodies. And Egypt wept for him for seventy days

Other versions

King James Version

And forty days were fulfilled for him; for so are fulfilled the days of those which are embalmed: and the Egyptians mourned for him threescore and ten days.

English Standard Version

Forty days were required for it, for that is how many are required for embalming. And the Egyptians wept for him seventy days.

New International Version

taking a full forty days, for that was the time required for embalming. And the Egyptians mourned for him seventy days.