12805
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 16632
- Proper Divisor Sum (Aliquot Sum)
- 3827
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9408
- Möbius Function
- -1
- Radical
- 12805
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 169
- 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
- Pseudoprimes to base 14.at n=36A020142
- Numbers k such that the continued fraction for sqrt(k) has period 41.at n=25A020380
- Numbers whose base-7 representation contains exactly four 2's.at n=28A043404
- Number of subsets S of {1,2,...,n} which contain a number that is greater than the sum of the other numbers in S.at n=30A095944
- Partial sums of orders of finite perfect groups (A060793).at n=15A121513
- Largest integer terms forming a self-convolution cube-root of a sequence (A132835) such that: A132835(n) <= 3*A132835(n-1) for n>0 with A132835(0)=1.at n=11A132836
- A122890 + A000012 - I, I = Identity matrix.at n=43A135723
- Numbers k such that continued fraction of (1 + sqrt(k))/2 has period 17.at n=35A146340
- a(n) = 12*n^2 - 8*n + 1.at n=33A185212
- a(n) = 13*n^2 - 16*n + 5.at n=32A202141
- a(n) = sigma(n)*Pell(n), where sigma(n) = A000203(n), the sum of divisors of n.at n=8A204271
- Total number of parts of multiplicity 9 in all partitions of n.at n=42A222709
- Triangle read by rows: T(n,k) is the coefficient A_k in the transformation Sum_{k=0..n} (k+1)*x^k = Sum_{k=0..n} A_k*(x-2)^k.at n=40A246797
- Number of 4 X n 0..1 arrays with every element equal to 0, 1, 3 or 6 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.at n=11A302637
- Numbers of the form p*q*r where p, q, r are distinct primes congruent to 1 mod 4 such that Legendre(p/q) = Legendre(p/r) = Legendre(q/r) = -1.at n=9A323271
- Sphenic numbers that are also the sum of three consecutive primes.at n=44A335969