666 (number) on 1/149 in base 10 has a magic total of 666. The prime factorization of 666 is 2 • 3 • 37. Also, 666 is the sum of squares of first seven primes: formula_2 The Roman numeral for 666, DCLXVI, has exactly one occurrence of all symbols whose value is less than 1000 in decreasing order (D = 500, C = 100, L = 50, X = 10, V = 5, I = 1). In the Textus Receptus manuscripts of the New Testament, the Book of Revelation () cryptically asserts 666 to be "man's number" or "the number of a
Roman numerals Arabic numerals being used for divisions and armies. In music, Roman numerals are used in several contexts: In pharmacy, Roman numerals are used in some contexts, including to denote "one half" and to mean "nothing". (See the sections below on "zero" and "fractions".) In photography, Roman numerals (with zero) are used to denote varying levels of brightness when using the Zone System. In seismology, Roman numerals are used to designate degrees of the Mercalli intensity scale of earthquakes. In sport the team containing the "top" players and representing a club or a school at the highest level in (say) rugby