11890
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 22680
- Proper Divisor Sum (Aliquot Sum)
- 10790
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4480
- Möbius Function
- 1
- Radical
- 11890
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 50
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that 19*2^k+1 is prime.at n=12A032359
- Numbers whose base-7 representation contains exactly four 4's.at n=27A043412
- Numbers k such that 1000k+1, 1000k+3, 1000k+7, 1000k+9 are all primes.at n=7A064962
- 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=23A090833
- Numbers k such that 6*k+1, 6*k+7, 6*k+13, 6*k+19 are consecutive primes.at n=11A090839
- Column 0 of triangle A105542, which equals the matrix square of triangle A105540.at n=17A105543
- a(n) = 9 + floor((3 + Sum_{j=1..n-1} a(j))/4).at n=32A120167
- a(n) = prime(n)_prime(n).at n=28A122622
- {2n+1}_{2n+1}.at n=54A122643
- G.f.: A(x) = (1 + 21*x + 3*x^2 - x^3)/(1-x)^5.at n=9A183066
- a(n) = Pell(n)*A109064(n) for n >= 1 with a(0)=1.at n=10A205884
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and 2w^2<=x^2+y^2.at n=27A211806
- Numbers k that are the product of four distinct primes such that x^2+y^2 = k has integer solutions.at n=14A248712
- Number of (n+2) X (3+2) 0..3 arrays with every consecutive three elements in every row and column not having exactly two distinct values, and in every diagonal and antidiagonal having exactly two distinct values, and new values 0 upwards introduced in row major order.at n=18A253020
- Total sum T(n,k) of number of lambda-parking functions of partitions lambda of n into distinct parts with largest part k; triangle T(n,k), k>=0, k<=n<=k*(k+1)/2, read by columns.at n=54A265019
- p-INVERT of (1,0,0,0,0,1,0,0,0,0,0,0,...), where p(S) = 1 - S^2.at n=42A292403
- Duplicate of A090839.at n=11A296055
- Numbers k such that lcm(1,2,3,...,k)/23 equals the denominator of the k-th harmonic number H(k).at n=9A342351
- Distinct values of A378664(k) in the order of appearance, when k ranges over those primitively abundant numbers k for which A378664(k) is less than the largest proper divisor of k.at n=17A378740