Exodus 1:5
And all the souls that came out of the loins of Jacob were seventy souls: for Joseph was in Egypt already.
Cross-reference
Genesis 46:26
Parallel
Genesis 46:26 reports 66 direct descendants who came to Egypt, a subset of the 70 total in Exodus 1:5.
Genesis 46:27
Parallel
Genesis 46:27 also states that seventy persons of Jacob came to Egypt, confirming the number.
Deuteronomy 10:22
Allusion
Deuteronomy 10:22 recalls the seventy who went to Egypt and God's multiplication, echoing Exodus 1:5.
Deuteronomy 26:5
Allusion
Deuteronomy 26:5 recalls the small beginning in Egypt, referring back to the seventy of Exodus 1:5.