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 Again - 400 () and 900 () follow the standard subtractive pattern. In the absence of a standard symbols for 5,000 and 10,000 the pattern breaks down at this point - in modern usage is repeated up to three times. The Romans had several different methods for indicating larger numbers, but for practical purposes Roman Numerals for numbers larger than 3,000 are seldom if ever used nowadays, and this suffices. Many numbers include hundreds, units and tens. The Roman numeral system being basically decimal, each power of ten is added in descending sequence from left to right, as with Arabic