9540
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 29484
- Proper Divisor Sum (Aliquot Sum)
- 19944
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2496
- Möbius Function
- 0
- Radical
- 1590
- Omega Function (Ω)
- 6
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 104
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = A188491(n+1) - A188494(n) - A002526(n).at n=10A002528
- a(n) = Sum_{k=1..n-1} lcm(k,n-k).at n=45A006580
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite TON = Theta-1 Nan[AlnSi24-nO48] starting with a T1 atom.at n=12A019243
- a(n) = Sum_{k=1..n} floor((n/k) * floor((n/k) * floor(n/k))).at n=19A024922
- Bessel polynomial {y_n}''(-3).at n=4A065948
- Numbers k such that prime(k+2)-(k+2)*tau(k+2) = prime(k-2)-(k-2)*tau(k-2) where tau(k) = A000005(k) is the number of divisors of k.at n=33A067354
- Sum of numbers in n-th upward diagonal of triangle in A079823.at n=39A079824
- Group the natural numbers such that the n-th group sum is divisible by prime(n): (1, 2, 3), (4, 5), (6, 7, 8, 9), (10, 11), (12, 13, 14, 15, 16, 17, 18, 19, 20, 21), ... Sequence contains the sum of the terms in the n-th group.at n=15A086491
- sigma(n) plus the n-th prime gives a square.at n=39A114082
- Number of peaks in all hill-free Dyck paths of semilength n (a Dyck path is hill-free if it has no peaks at level 1).at n=9A114515
- Number of binary strings of length n with no substrings equal to 000, 010, or 111.at n=41A164317
- Numbers k such that k^2 +-11 are primes.at n=30A176683
- E.g.f. satisfies: A'(x) = [A(x)^2 + A(x)^3]/(x^2 + x^3).at n=6A179495
- Sums of knight's moves over the square |i|+|j|<=n on infinite chessboard.at n=25A183053
- Numbers n for which the terms of the multiplicative sequence {n^2/A049417(n)} are integers.at n=20A185288
- Sum of the first k-1 numbers in the k-th column of the natural number array A000027, by antidiagonals.at n=20A185788
- Coefficient of x in the reduction of the n-th Fibonacci polynomial by x^3->x^2+2x+1.at n=12A192773
- Numbers a = b + c where a, b, and c contain the same decimal digits.at n=20A203024
- Number of nX4 0..2 arrays with row sums equal and column sums unequal to adjacent columns.at n=2A203487
- T(n,k)=Number of nXk 0..2 arrays with row sums equal and column sums unequal to adjacent columns.at n=17A203491