9141
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13344
- Proper Divisor Sum (Aliquot Sum)
- 4203
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5520
- Möbius Function
- -1
- Radical
- 9141
- 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
- 34
- 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
- no
- Odd
- yes
Appears in sequences
- Tetrahedral numbers written backwards.at n=43A004161
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DDR = Deca-dodecasil 3R[Si120O240]qR starting with a T6 atom.at n=12A019108
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 8.at n=40A051973
- a(1) = 1; for n >= 1, a(n+1) is smallest number such that the sums of any one, two or three of a(1), ..., a(n) are distinct (repetitions not allowed).at n=20A062065
- Numbers which yield a prime whenever a 1 is inserted anywhere in them (including at the beginning or end).at n=60A068679
- Number of ways to partition 2*n into distinct positive integers not greater than n.at n=30A079122
- Coefficients in asymptotic expansion of normal probability function.at n=7A097397
- Start with 1 and repeatedly reverse the digits and add 65 to get the next term.at n=16A118163
- Number of ways to place zero or more nonadjacent 0,0 1,0 1,1 2,0 3,1 polyhexes in any orientation on a planar nXnXn triangular grid.at n=5A155234
- a(n) = Sum_{j=1..prime(n)-1} floor(j^2/prime(n)).at n=38A165993
- a(0)=0, a(1)=0; for n>1, a(n) = a(n-1) + n*a(n-2) + 1.at n=10A185308
- Number of ordered quadruples of distinct pairwise coprime positive integers with largest element n; also first differences of A015623.at n=58A185348
- G.f. satisfies: A(x) = 1 + x*A(x)^5*A(x*A(x)^5).at n=5A215507
- Composite numbers and 1 which yield a prime whenever a 1 is inserted anywhere in them, including at the beginning or end.at n=42A216165
- Number of n X 3 arrays with each row a permutation of 1..3 having at least as many downsteps as the preceding row, with rows in lexicographically nonincreasing order.at n=35A222001
- Number of arrays of median of three adjacent elements of some length-5 0..n array, with no adjacent equal elements in the latter.at n=19A229013
- Number of equilateral triangles bounded by the sides and diagonals of a regular 3n-gon.at n=10A238822
- First differences of A263096.at n=72A263097
- Solution of the complementary equation a(n) = 2*a(n-1) - a(n-2) + b(n-1) + 2, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=33A294870
- Numbers k such that A334943(k) = 1.at n=12A335773