11951
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13680
- Proper Divisor Sum (Aliquot Sum)
- 1729
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10368
- Möbius Function
- -1
- Radical
- 11951
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- Numbers k such that sigma(k) = sigma(k+12).at n=40A015882
- Numerator of n*(n-2)*(2*n-1)/(2*(n-1)).at n=17A022997
- Numbers ending with '1' that are the difference of two positive cubes.at n=39A038856
- Numbers whose base-4 representation contains exactly four 2's and three 3's.at n=10A045156
- a(n) = smallest m >= 1 such that Sum_{k=1..m} log(k)/k >= n.at n=44A092753
- Fourth column of (1,5)-Pascal triangle A096940.at n=36A096941
- Multiples of 19 containing a 19 in their decimal representation.at n=21A121039
- Number of n X n symmetric binary matrices containing no more than five 1s in any 3 X 3 sub-block.at n=5A139015
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, -1, 1), (0, 0, 1), (0, 1, -1), (1, 0, -1)}.at n=10A148502
- A156977/3.at n=6A164565
- Numbers k that divide 10^(k+1)-1.at n=36A175203
- Numbers n such that the digits of sigma(n) are exactly the same (albeit in different order) as the digits of phi(n), in base 10.at n=18A175795
- Numbers k such that 2^(k+1) == 1 (mod k).at n=19A187787
- 17 times triangular numbers.at n=37A195037
- Composite numbers n such that b^(n+1) == 1 (mod n) for every b coprime to n.at n=10A208728
- Number of (n+1)X(1+1) 0..1 arrays x(i,j) with row sums sum{j^2*x(i,j), j=1..1+1} nondecreasing, and column sums sum{i^2*x(i,j), i=1..n+1} nondecreasing.at n=43A232871
- Generalized Lucas-Carmichael numbers for D=9697.at n=36A290560
- Regular triangle where T(n,k) is the number of inequivalent colorings of free pure symmetric multifunctions (with empty expressions allowed) with n positions and k leaves.at n=48A304485
- Partial sums of A304910.at n=37A304913
- Chebyshev pseudoprimes to base 2: composite numbers k such that T(k, 2) == 2 (mod k), where T(k, x) is the k-th Chebyshev polynomial of the first kind.at n=38A330206