Which was the number that caused the hypothetical death of Hippasus of Metapontum?

The square root of two first appeared in a time where the Pythagorean School was considered the mainstream. Known from the famous Theorem, it also regarded the numbers as the extension of the deities. From their point of view, the numbers should not be chaotic so the Pythagorean Society only accepted the existence of positive rational numbers like 3 or 1/2. Until Hippasus of Metapontum (530 – 450 BC) discovered the √2 by applying the Theorem of his master in a square of side 1. The diagonal of this square cannot be expressed as the ratio of two integers, so it is an irrational number.

One of the possible causes of Hippasus's death is that the Pythagoreans tried to hide the results of the √2 by throwing him overboard on a sea voyage.