843
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1128
- Proper Divisor Sum (Aliquot Sum)
- 285
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 560
- Möbius Function
- 1
- Radical
- 843
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- yes
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 41
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- achthundertdreiundvierzig· ordinal: achthundertdreiundvierzigste
- English
- eight hundred forty-three· ordinal: eight hundred forty-third
- Spanish
- ochocientos cuarenta y tres· ordinal: 843º
- French
- huit cent quarante-trois· ordinal: huit cent quarante-troisième
- Italian
- ottocentoquarantatre· ordinal: 843º
- Latin
- octingenti quadraginta tres· ordinal: 843.
- Portuguese
- oitocentos e quarenta e três· ordinal: 843º
Appears in sequences
- Lucas numbers (beginning with 1): L(n) = L(n-1) + L(n-2) with L(1) = 1, L(2) = 3.at n=13A000204
- Flavius Josephus's sieve: Start with the natural numbers; at the k-th sieving step, remove every (k+1)-st term of the sequence remaining after the (k-1)-st sieving step; iterate.at n=32A000960
- A self-generating sequence: a(1)=1, a(2)=2, a(n+1) chosen so that a(n+1)-a(n-1) is the first number not obtainable as a(j)-a(i) for 1<=i<j<=n.at n=33A001149
- Number of partitions of n into parts 2, 3, 4, 5, 6, 7.at n=42A001996
- Numbers k such that (k^2 + k + 1)/19 is prime.at n=26A002643
- a(n) = round(n*phi^14), where phi is the golden ratio, A001622.at n=1A004949
- a(n) = ceiling(n*phi^14), where phi is the golden ratio, A001622.at n=1A004969
- a(n) = 3*a(n-2) - a(n-4), a(0)=2, a(1)=1, a(2)=3, a(3)=2. Alternates Lucas (A000032) and Fibonacci (A000045) sequences for even and odd n.at n=14A005247
- Bisection of Lucas numbers: a(n) = L(2*n) = A000032(2*n).at n=7A005248
- a(n+1) = a(n)-th composite number, with a(0) = 1.at n=17A006508
- Number of subwords of length n in infinite word generated by a -> aab, b -> b.at n=44A006697
- Binary palindromes: numbers whose binary expansion is palindromic.at n=57A006995
- Inverse Moebius transform applied twice to squares.at n=28A007433
- Coordination sequence T1 for Zeolite Code AFY.at n=24A008029
- Coordination sequence T4 for Zeolite Code DOH.at n=18A008081
- Coordination sequence T4 for Zeolite Code EMT.at n=24A008089
- Coordination sequence T2 for Zeolite Code MTT.at n=18A008190
- Coordination sequence T3 for Zeolite Code MTT.at n=18A008191
- Coordination sequence T1 for Milarite.at n=18A008256
- a(0) = 1, a(n) = n^2 + 2 for n > 0.at n=29A010000