12879
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 19656
- Proper Divisor Sum (Aliquot Sum)
- 6777
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8424
- Möbius Function
- 0
- Radical
- 159
- Omega Function (Ω)
- 6
- 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
- yes
- 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 partitions into non-integral powers.at n=9A000347
- Number of partitions of n in which the least part is odd.at n=34A026804
- a(n) = (2*n+1) * (4*n-1).at n=40A033566
- Numbers n such that 69*2^n-1 is prime.at n=43A050560
- Numbers n such that n | 11^n + 10^n + 9^n + 8^n + 7^n.at n=44A057251
- Numbers which contain exactly the same digits (with the correct multiplicity) in 3 different smaller bases.at n=21A059828
- Triangle with T(n,k) = k*E(n,k) where E(n,k) are Eulerian numbers A008292.at n=30A065826
- Lesser of two consecutive numbers each divisible by a fourth power.at n=24A068782
- Numbers k such that k divides tau(k) and k+1 divides tau(k+1), where tau(k)=A000594(k) is Ramanujan's tau function; i.e., k and k+1 are in A063938.at n=33A079334
- a(n) = number of reverse alternating fixed-point-free involutions w on 1,2,...,2n, i.e., w(1) < w(2) > w(3) < w(4) > ... < w(2n), w^2=1 and w(i) != i for all i.at n=9A115455
- Numbers of the form 110 + p^2. (where p is a prime).at n=29A138693
- Nine times hexagonal numbers: a(n) = 9*n*(2*n-1).at n=27A152994
- Integers of the form A164577(k)/3.at n=25A164619
- 1/36 the number of (n+2) X 3 0..2 arrays with each 3 X 3 subblock containing two of one value, two of another, and five of the last.at n=4A184449
- 1/36 the number of (n+2)X7 0..2 arrays with each 3X3 subblock containing two of one value, two of another, and five of the last.at n=0A184453
- T(n,k)=1/36 the number of (n+2)X(k+2) 0..2 arrays with each 3X3 subblock containing two of one value, two of another, and five of the last.at n=10A184457
- T(n,k)=1/36 the number of (n+2)X(k+2) 0..2 arrays with each 3X3 subblock containing two of one value, two of another, and five of the last.at n=14A184457
- Nonprime numbers with a sum of nonprime divisors which is a perfect square.at n=26A194580
- a(2) = 1, then (p-1)*(p-4)/2, with p = prime(n), n > 2.at n=36A200050
- Number of (w,x,y) with all terms in {0,...,n} and w>floor((x+y)/3).at n=26A212974