17865
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
- 31044
- Proper Divisor Sum (Aliquot Sum)
- 13179
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9504
- Möbius Function
- 0
- Radical
- 5955
- 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
- 141
- 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
- Base-8 Armstrong or narcissistic numbers (written in base 10).at n=16A010354
- pi(n) is a power of 2, where pi(n) = A000720(n) is the number of primes <= n.at n=45A073798
- Number of permutations of length n which avoid the patterns 1234, 2431, 3412.at n=11A116755
- Triangle read by rows: T(n, k) = binomial(n-1, k-1)*A008292(n, k).at n=23A141686
- Triangle read by rows: T(n, k) = binomial(n-1, k-1)*A008292(n, k).at n=25A141686
- Base-11 Armstrong or narcissistic numbers (written in base 10).at n=22A161948
- Base 8 perfect digital invariants (written in base 10): numbers equal to the sum of the k-th powers of their base-8 digits, for some k.at n=37A162231
- G.f.: Sum_{n>=0} a(n)*x^n/(1+x)^(3*n^2) = 1+x.at n=5A177449
- Number of triple-rises in all length n left factors of Dyck paths (triple-rise = three consecutive (1,1)-steps).at n=15A191787
- Centered 44-gonal numbers.at n=28A195318
- a(n) = Sum_{i=0..n} digsum_7(i)^3, where digsum_7(i) = A053828(i).at n=53A231678
- Pseudoprimes to base 8 that are not squarefree.at n=10A243090
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 419", based on the 5-celled von Neumann neighborhood.at n=29A272047
- Numbers with a minimum of 6 polygonal roots, excluding itself.at n=19A275256
- E.g.f. satisfies A(x) = 1 + x*A(x)*exp(x*A(x)^4).at n=5A377550
- E.g.f. A(x) satisfies A(x) = 1/( 1 - 3*x*exp(x*A(x)) )^(1/3).at n=5A380039
- Triangle read by rows: T(n,k) is the number of rooted ordered trees with node weights summing to n, where the root has weight 0, all internal nodes have weight 1, and leaf nodes have weights in {1,...,k}.at n=48A384685