11982
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 23976
- Proper Divisor Sum (Aliquot Sum)
- 11994
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 3992
- Möbius Function
- -1
- Radical
- 11982
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- Number of numbers k which give 1 after applying exactly n iterations of the 3k+1 algorithm (if a number is even, divide it by 2; if it is odd, multiply by 3 and add 1). This total includes numbers k which also give 1 for a smaller number of iterations (i.e., for this sequence we do not assume the algorithm halts when 1 is reached).at n=39A082538
- a(n) is the number of binary strings of length n such that no subsequence of length 5 or less contains 4 or more ones.at n=14A125513
- a(n) = p(n)*p(n+2)-p(n+1), where p(n) is the n-th prime.at n=27A152530
- Square array read by antidiagonals: T(m,n) is the number of L-convex polyominoes with m rows and n columns.at n=49A181370
- Square array read by antidiagonals: T(m,n) is the number of L-convex polyominoes with m rows and n columns.at n=50A181370
- Number of partitions of 2^n into binomial coefficients C(n,k).at n=10A225860
- Round(-1/n + 1/log((2n+1)/(2n-1))).at n=9A227513
- Number of (n+1) X (n+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).at n=3A234556
- Number of (n+1) X (4+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).at n=3A234560
- T(n,k) is the number of (n+1) X (k+1) 0..4 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings).at n=24A234564
- Expansion of 1/G(0) where G(k) = 1 - q/(1 - q - q^3 / G(k+1) ).at n=12A238438
- Irregular triangle read by rows: T(n,k) is the number of sensed 3-connected planar maps with n >= 4 faces and k >= 4 vertices.at n=43A239893
- Irregular triangle read by rows: T(n,k) is the number of sensed 3-connected planar maps with n >= 4 faces and k >= 4 vertices.at n=55A239893
- Least number x such that x^n has n digits equal to k. Case k=4.at n=17A285451
- Numbers k such that (26*10^k - 413)/9 is prime.at n=17A293593
- Number of partitions of integer partitions of n where all parts have the same length.at n=23A319066
- Nearest integer to 1/delta_n, where the delta_n are coefficients in Sitaramachandrarao's series for the Riemann zeta function.at n=16A330552
- Main diagonal of A332361.at n=17A332362
- Expansion of 1/(1 - 9*x/(1 - x))^(1/3).at n=5A361375