1081
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1152
- Proper Divisor Sum (Aliquot Sum)
- 71
- 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
- 1012
- Möbius Function
- 1
- Radical
- 1081
- 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
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 137
- Smith Number
- no
- Vampire 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
Appears in sequences
- Padovan sequence (or Padovan numbers): a(n) = a(n-2) + a(n-3) with a(0) = 1, a(1) = a(2) = 0.at n=31A000931
- Genus of modular group Gamma(n) = genus of modular curve Chi(n).at n=31A001767
- Genus of modular group Gamma(n) = genus of modular curve Chi(n).at n=34A001767
- Related to Zarankiewicz's problem.at n=44A001841
- Number of simplices in barycentric subdivision of n-simplex.at n=5A002050
- From a Goldbach conjecture: the location of records in A185091.at n=9A002091
- a(n) = round(n*phi^8), where phi is the golden ratio, A001622.at n=23A004943
- a(n) = ceiling(n*phi^8), where phi is the golden ratio, A001622.at n=23A004963
- a(0) = 0, a(1) = a(2) = a(3) = 1; thereafter, a(n) = a(n-1) + a(n-2) + a(n-4).at n=15A005251
- Number of achiral trees with n nodes.at n=15A005629
- Bitriangular permutations.at n=4A006230
- Coefficients of period polynomials.at n=13A006308
- Number of strict 7th-order maximal independent sets in cycle graph.at n=46A007394
- a(n) is the smallest positive number such that the sum of A001032(n) consecutive squares starting with a(n)^2 is a square.at n=51A007475
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=18A007697
- Coordination sequence T1 for Zeolite Code ATV.at n=21A008043
- Coordination sequence T2 for Zeolite Code MEI.at n=24A008147
- Coordination sequence T3 for Zeolite Code MFI.at n=21A008166
- Coordination sequence T8 for Zeolite Code MFI.at n=21A008171
- Coordination sequence T3 for Zeolite Code NES.at n=21A008207