6975
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 12896
- Proper Divisor Sum (Aliquot Sum)
- 5921
- 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
- 3600
- Möbius Function
- 0
- Radical
- 465
- Omega Function (Ω)
- 5
- 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
- 132
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Number of stable trees with n nodes.at n=14A003426
- Number of paraffins.at n=29A005997
- Odd numbers k that divide phi(k)*sigma(k).at n=14A015706
- Ordered sequence of distinct terms of the form floor(x^i * floor(x^j)), i,j >= 0, where x = sqrt(5).at n=32A022770
- Expansion of 1/((1-4x)(1-5x)(1-6x)(1-12x)).at n=3A028114
- Odd 9-gonal (or enneagonal) numbers.at n=22A028991
- a(n) = (2*n+1)*(7*n+1).at n=22A033572
- Numbers k that divide sigma(k) * phi(k) and are not divisible by 6.at n=35A047630
- a(n+1) = a(n)^2 + n*(n+3)*a(n).at n=3A051481
- T(n,n-4), where T is the array in A055830.at n=30A055831
- Numbers k such that the Lucas Aurifeuillian primitive part B of Lucas(k) is prime.at n=49A061443
- Ooguri-Vafa invariants of disk domain wall degeneracies for brane I in the O(K) -> P^1 X P^1 geometry.at n=2A061614
- Numbers k such that k divides the (right) concatenation of all numbers <= k written in base 19 (most significant digit on right).at n=20A061948
- Nearest integer to log(n^n)^(1 + log(log(1 + n))).at n=20A062480
- Number of unrooted planar 2-constellations with n digons. Also number of n-edge unrooted planar Eulerian maps with bicolored faces.at n=7A090371
- a(n) = n^2*(2*n+1).at n=15A099721
- Enneagonal numbers divisible by 9.at n=10A117796
- Expansion of g.f.: -x*(1 - 2*x + 6*x^2 - 2*x^3 + x^4)/((1-x)^3*(1+x)^4).at n=29A122576
- a(n) = n*floor(n/2)^2.at n=31A122656
- a(n) = (1/2)*(n^4 + 11*n^3 + 53*n^2 + 97*n + 54).at n=9A129026