70 (number)

70 (seventy) is the natural number following 69 and preceding 71. 70 is: a sphenic number because its factors are 3 distinct primes. a Pell number. the seventh pentagonal number. the fourth tridecagonal number. the fifth pentatope number. the number of ways to choose 4 objects out of 8 if order does not matter. This makes it a central binomial coefficient. the smallest weird number, a natural number that is abundant but not semiperfect. a palindromic number in bases 9 (779), 13 (5513) and 34 (2234). a Harshad number in bases 6, 8, 9, 10, 11, 13, 14, 15 and 16. an Erdős–Woods number, since it is possible to find sequences of 70 consecutive integers such that each inner member shares a factor with either the first or the last member. The sum of the first 24 squares starting from 1 is 70^2 = 4900, i.e. a square pyramidal number. This is the only non trivial solution to the cannonball problem and relates 70 to the Leech lattice and thus string theory. 70 is the atomic number of ytterbium, a lanthanide Messier object M70, a magnitude 9.0 globular cluster in the constellation Sagittarius The New General Catalogue object NGC 70, a magnitude 13.4 spiral galaxy in the constellation Andromeda In Jewish tradition: Seventy souls went down to Egypt to begin the Hebrews' Egyptian exile (). There is a core of 70 nations and 70 world languages, paralleling the 70 names in the Table of Nations. There were 70 men in the Great Sanhedrin, the Supreme Court of ancient Israel. (Sanhedrin 1:4.) According to the Jewish Aggada, there are 70 perspectives ("faces") to the Torah (Numbers Rabbah 13:15). Seventy elders were assembled by Moses on God's command in the desert (). allots three score and ten (70 years) for a man's life, and the Mishnah attributes that age to "strength" (Avot 5:32), as one who survives that age is described by the verse as "the strong". Ptolemy II Philadelphus ordered 72 Jewish elders to translate the Torah into Greek; the result was the Septuagint (from the Latin for "seventy").