11978
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18468
- Proper Divisor Sum (Aliquot Sum)
- 6490
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5824
- Möbius Function
- -1
- Radical
- 11978
- 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
- 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
- Coordination sequence for Cr3Si, Si position.at n=28A009927
- Coordination sequence for Ni2In, Position Ni1 and In.at n=33A009941
- Number of matchings in graph C_{3} X P_{n}.at n=5A033515
- Numbers k such that 295*2^k + 1 is prime.at n=23A053364
- a(n) is the start of the first arithmetic progression with common difference n of n numbers with the same prime signature.at n=7A087306
- Number of partitions of n such that multiplicities of parts are all relatively prime to n.at n=43A100495
- Triangle read by rows: T(n,k) is the number of hill-free Schroeder paths of length 2n and having k ascents (n>=1; 0<=k<=n-1). A Schroeder path of length 2n is a lattice path from (0,0) to (2n,0) consisting of U=(1,1), D=(1,-1) and H=(2,0) steps and never going below the x-axis. A hill is a peak at height 1. An ascent in a Schroeder path is a maximal sequence of consecutive U steps.at n=38A114706
- Denominators of Egyptian fraction for Pi-3 whose partial sums are the convergents.at n=2A156618
- a(n) = 9*11^n - 1.at n=3A199029
- Number of ways to cut an n X n square into squares with integer sides, reduced for symmetry, where the orbits under the symmetry group of the square, D4, have 2 elements.at n=10A226979
- Composite squarefree numbers n such that p-d(n) divides n-d(n), where p are the prime factors of n and d(n) the number of divisors of n.at n=15A228300
- Expansion of Product_{k>=1} (1 + x^(3*k-1))^(3*k-1).at n=34A262948
- Array read by antidiagonals: T(m,n) is the number of matchings in the stacked prism graph C_m X P_n.at n=23A287428
- Sum of the odd parts in the partitions of n into 5 parts.at n=35A309545
- Centered heptagonal numbers which are sphenic numbers.at n=3A360183