12916
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 22610
- Proper Divisor Sum (Aliquot Sum)
- 9694
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6456
- Möbius Function
- 0
- Radical
- 6458
- Omega Function (Ω)
- 3
- 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
- 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
- 76
- 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
- yes
- Odd
- no
Appears in sequences
- Central factorial numbers: 1st subdiagonal of A008956.at n=3A001824
- Triangle of central factorial numbers |4^k t(2n+1,2n+1-2k)| read by rows (n>=0, k=0..n).at n=13A008956
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers), t = A014306.at n=34A024477
- Centered 15-gonal numbers: a(n) = (15*n^2 - 15*n + 2)/2.at n=41A069128
- Triangle T(n,k) defined by the generating function cosh(sqrt(y)*arcsin(x)) + sqrt(y)*sinh(sqrt(y)*arcsin(x)) - 1 = Sum_{n>=1} Sum_{k=1..n} T(n,k)*y^k *x^n/n!.at n=21A091885
- Least positive k such that k * [RSA-640]^n - 1 is prime, where RSA-640 is the 193 decimal digit RSA challenge number A391940(14).at n=19A108573
- Number of ways to partition 1 into reduced fractions i/j with j <= n.at n=18A119983
- Numerator of Sum_{k=1..n} 1/(2*k-1)^2.at n=3A120268
- Triangle T(n,k) defined by the generating function: exp(y*arcsin(x))-1 = Sum_{n>=1} (Sum_{k=1..n} T(n,k)*y^k)*x^n/n!.at n=38A121408
- Maximum cycle size in range [A014137(n-1)..A014138(n-1)] of permutation A125987/A125988.at n=11A126296
- Smallest number whose ninth power has at least n digits.at n=37A130083
- Table of the number of (n,k)-Riordan complexes, read by rows.at n=11A160563
- Third column (negated) of triangle in A182971.at n=6A184878
- Define a pair of sequences c_n, d_n by c_0=0, d_0=1 and thereafter c_n = c_{n-1}+d_{n-1}, d_n = c_{n-1}+4*n+2; sequence here is d_n.at n=16A192750
- G.f.: A(x,y) = Sum_{n>=0} n!*x^n*y^n * Product_{k=1..n} (1+y + 2*k*x*y) / (1 + (1+y)*k*x + 2*k^2*x^2*y).at n=38A221987
- G.f.: A(x,y) = Sum_{n>=0} n!*x^n*y^n * Product_{k=1..n} (1+y + 2*k*x*y) / (1 + (1+y)*k*x + 2*k^2*x^2*y).at n=42A221987
- Number of partitions of n such that (greatest part) - (least part) <= number of parts.at n=36A237831
- Number of partitions of n with difference -8 between the number of odd parts and the number of even parts, both counted without multiplicity.at n=38A242684
- Number of connected graphs with n nodes that are chordal and have no subgraph isomorphic to the bull graph.at n=13A243798
- a(0) = 12, after which, if (2*a(n-1)) - 1 = product_{k >= 1} (p_k)^(c_k) then a(n) = product_{k >= 1} (p_{k-1})^(c_k), where p_k indicates the k-th prime, A000040(k).at n=35A246343