11898
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
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 25818
- Proper Divisor Sum (Aliquot Sum)
- 13920
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3960
- Möbius Function
- 0
- Radical
- 3966
- 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
- 99
- 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
- Erroneous version of A174313.at n=8A002933
- a(n) = Sum_{k=1..n} ceiling(k^4/n).at n=14A014816
- Expansion of 1/((1-5x)(1-7x)(1-9x)(1-12x)).at n=3A028186
- Molien series for complete weight enumerator of self-dual code over GF(5).at n=37A028344
- Total number of smallest parts in all partitions of n into odd parts.at n=42A092268
- Positions where A109890(n) = Sum_{i = 1..n-1} A109890(i).at n=27A111315
- Triangle, rows = inverse binomial transforms of A117938 columns.at n=38A117937
- Multiples of 18 containing a 18 in their decimal representation.at n=31A121038
- 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, 0, 1), (0, 0, 1), (0, 1, 0), (1, -1, -1)}.at n=9A149829
- Number of n-step walks on hexagonal lattice (no points repeated, no adjacent points unless consecutive in path).at n=8A174313
- a(1)=4. a(n) = a(n-1) + n, if a(n-1)+n is composite. Otherwise a(n) = a(n-1)*n.at n=16A175459
- Numbers m such that there is a k with 2^m/(m+1) < binomial(m,k) <= 2^m/m and k < m/2.at n=45A229485
- Trisection of A107926: The least number k such that there are primes p and q with p - q = 6*n+4, p + q = k, and p the least such prime >= k/2.at n=26A234956
- Palindromic numbers in bases 5 and 8 written in base 10.at n=12A259383
- Numbers k such that lcm(1,2,3,...,k)/23 equals the denominator of the k-th harmonic number H(k).at n=17A342351
- Number of n-digit left- or right-truncatable primes with no consecutive zero digits.at n=41A346662
- a(n) is the number of squarefree composite k with lpf(k) = prime(n) such that m <= Omega(k), where lpf = A020639, m = floor(log k / log lpf(k)), and Omega = A001222.at n=9A377793
- Indices where the cumulative sum of cos(2k+1)^(2k+1) reaches a record low value.at n=29A389560