ב 2 + ן 50 = 52. With the final nun at 700 (mispar gadol) it is 702.
Meaning
Ben is 'son', and its 52 is the fourth filling of the Tetragrammaton — the one spelled with hehs, the BEN expansion — so that 'son' and the name's most contracted form are the same number. The Kabbalists read the four fills as the four worlds, and ben as the number of the lowest: the son is the name at its densest, the point where it becomes a world.