the sum of the powers of 3 from 0 to 4, so a repunit in ternary. Furthermore, 121 is the only square of the form , where p is prime (3, in this case).[1]
the sum of three consecutive prime numbers (37 + 41 + 43).
As , it provides a solution to Brocard's problem. There are only two other squares known to be of the form . Another example of 121 being one of the few numbers supporting a conjecture is that Fermat conjectured that 4 and 121 are the only perfect squares of the form (with x being 2 and 5, respectively).[2]
In decimal, it is a Smith number since its digits add up to the same value as its factorization (which uses the same digits) and as a consequence of that it is a Friedman number (). But it cannot be expressed as the sum of any other number plus that number's digits, making 121 a self number.
^Rule 1.1 2015-01-18 at the Wayback Machine, American Cribbage Congress, retrieved 6 September 2011
January 01, 1970
number, hundred, twenty, natural, number, following, preceding, list, numbersintegers, cardinalone, hundred, twenty, oneordinal121st, hundred, twenty, first, factorization112divisors1, 121greek, numeralΡΚΑ, roman, numeralcxxibinary11110012ternary111113senary32. 121 one hundred and twenty one is the natural number following 120 and preceding 122 120 121 122 120 121 122 123 124 125 126 127 128 129 List of numbersIntegers 0 100 200 300 400 500 600 700 800 900 Cardinalone hundred twenty oneOrdinal121st one hundred twenty first Factorization112Divisors1 11 121Greek numeralRKA Roman numeralCXXIBinary11110012Ternary111113Senary3216Octal1718DuodecimalA112Hexadecimal7916 Contents 1 In mathematics 2 In other fields 3 See also 4 ReferencesIn mathematics editOne hundred and twenty one is a square 11 times 11 the sum of the powers of 3 from 0 to 4 so a repunit in ternary Furthermore 121 is the only square of the form 1 p p 2 p 3 p 4 displaystyle 1 p p 2 p 3 p 4 nbsp where p is prime 3 in this case 1 the sum of three consecutive prime numbers 37 41 43 As 5 1 121 displaystyle 5 1 121 nbsp it provides a solution to Brocard s problem There are only two other squares known to be of the form n 1 displaystyle n 1 nbsp Another example of 121 being one of the few numbers supporting a conjecture is that Fermat conjectured that 4 and 121 are the only perfect squares of the form x 3 4 displaystyle x 3 4 nbsp with x being 2 and 5 respectively 2 It is also a star number a centered tetrahedral number and a centered octagonal number nbsp A Chinese checkers board has 121 holes In decimal it is a Smith number since its digits add up to the same value as its factorization which uses the same digits and as a consequence of that it is a Friedman number 11 2 displaystyle 11 2 nbsp But it cannot be expressed as the sum of any other number plus that number s digits making 121 a self number In other fields edit121 is also The electricity emergency telephone number in Egypt The number for voicemail for mobile phones on the Vodafone network 3 The undiscovered chemical element unbiunium has the atomic number 121 The official end score for cribbage 4 The pennant number of RTS Moskva the Russian Navy s Black Sea flagship which was damaged beyond repair on April 13 2022 See also editList of highways numbered 121 United States House of Representatives House Resolution 121 United Nations Security Council Resolution 121References edit Ribenboim Paulo 1994 Catalan s conjecture are 8 and 9 the only consecutive powers Boston Academic Press ISBN 0 12 587170 8 OCLC 29671943 Wells D The Penguin Dictionary of Curious and Interesting Numbers London Penguin Group 1987 136 Vodafone Calling and messaging Rule 1 1 Archived 2015 01 18 at the Wayback Machine American Cribbage Congress retrieved 6 September 2011 Retrieved from https en wikipedia org w index php title 121 number amp oldid 1205803992, wikipedia, wiki, book, books, library,
