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
Chinese numerals seven, short for year nineteen sixty seven, a common Chinese shorthand for the Hong Kong 1967 leftist riots. In the same way that Roman numerals were standard in ancient and medieval Europe for mathematics and commerce, the Chinese formerly used the rod numerals, which is a positional system. The Suzhou numerals () system is a variation of the Southern Song rod numerals. Nowadays, the "huāmǎ" system is only used for displaying prices in Chinese markets or on traditional handwritten invoices. There is a common method of using of one hand to signify the numbers one to ten. While the five