1131
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 1680
- Proper Divisor Sum (Aliquot Sum)
- 549
- 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
- 672
- Möbius Function
- -1
- Radical
- 1131
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 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
- 36
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- E.g.f. satisfies A'(x) = A(x/(1-x)).at n=6A001063
- a(n) = least value of m for which Liouville's function A002819(m) = -n.at n=41A002053
- Odd squarefree numbers with an odd number of prime factors that have no prime factors greater than 31.at n=47A002556
- Number of bipartite partitions.at n=9A002763
- Numbers that are divisible by the product of their digits.at n=39A007602
- Numbers that contain only 1's, 2's and 3's.at n=45A007932
- Expansion of (1+x^2)(1+x^4)/((1-x)^2*(1-x^2)*(1-x^3)).at n=21A007979
- Coordination sequence T1 for Zeolite Code BIK.at n=20A008047
- Coordination sequence T2 for Zeolite Code BOG.at n=24A008050
- Coordination sequence T1 for Zeolite Code DAC.at n=21A008067
- Coordination sequence T1 for Zeolite Code LTL.at n=24A008138
- Coordination sequence T2 for Coesite.at n=18A008268
- Expansion of (1+x^8)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=42A008769
- Number of increasing sequences of addition chain type with maximal element n.at n=13A008928
- Coordination sequence T1 for Zeolite Code RSN.at n=22A009885
- Coordination sequence T2 for Zeolite Code RSN.at n=22A009886
- Coordination sequence T2 for Zeolite Code VNI.at n=21A009908
- Coefficients in expansion of Pi as Sum_{n>=1} a(n)/(n*n!*(n+1)!), as found by greedy algorithm.at n=37A011191
- [ n(n-1)(n-2)(n-3)/7 ].at n=11A011917
- Number of 7's in all the partitions of n into distinct parts.at n=49A015742