12925
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
- 12
- Divisor Sum
- 17856
- Proper Divisor Sum (Aliquot Sum)
- 4931
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9200
- Möbius Function
- 0
- Radical
- 2585
- Omega Function (Ω)
- 4
- 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
- 169
- 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 dissections of a convex (n+2)-gon into triangles and quadrilaterals by nonintersecting diagonals.at n=8A001002
- a(n) = (d(n)-r(n))/2, where d = A026043 and r is the periodic sequence with fundamental period (1,1,0,0).at n=39A026044
- Number of partitions of n that do not contain 10 as a part.at n=35A027344
- Numbers n such that n | 12^n + 11^n + 10^n + 9^n + 8^n.at n=36A057250
- Convoluted convolved Fibonacci numbers G_j^(9).at n=8A089096
- Numbers n such that 6n+5, 6n+11, 6n+17, 6n+23 are consecutive primes or 6n+1, 6n+7, 6n+13, 6n+19 are consecutive primes.at n=25A090833
- Numbers k such that 6*k+1, 6*k+7, 6*k+13, 6*k+19 are consecutive primes.at n=12A090839
- 45-gonal numbers: n*(43*n-41)/2.at n=24A098924
- a(n) = (7*n^3 + 6*n^2 + 5*n) / 6.at n=22A101165
- A130041(n) is the a(n)-th composite number.at n=13A130042
- Triangle T(n,m) read by rows, [A(x)]^m = Sum_{n>=m} T(n,m)*x^n, where A(x) satisfies A(x) = x/(1-A(x)-A(x)^2).at n=36A188111
- Position of 3^n in A051037 (5-smooth numbers).at n=40A188426
- Numbers k such that k divides 1 + Sum_{j=1..k} prime(j)^14.at n=33A232966
- Number of (7+2) X (n+2) 0..1 arrays with every 3 X 3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=10A254913
- Duplicate of A090839.at n=12A296055
- Number of nX4 0..1 arrays with every element equal to 0, 2, 4, 5 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=25A303321
- Numbers k such that all primes dividing the k-th composite number divide k as well.at n=35A368309
- Product of Fibonacci and self-convolution of Fibonacci numbers: a(n) = A000045(n+1)*A001629(n+1).at n=9A372015
- a(n) is the smallest number which can be represented as the sum of n distinct nonzero squares in exactly 2 ways, or -1 if no such number exists.at n=32A374287
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,0) = 0^n and T(n,k) = k * Sum_{r=0..n} binomial(n+r+k,r) * binomial(r,n-r)/(n+r+k) for k > 0.at n=53A378289