9804
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 24640
- Proper Divisor Sum (Aliquot Sum)
- 14836
- 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
- 3024
- Möbius Function
- 0
- Radical
- 4902
- Omega Function (Ω)
- 5
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 135
- 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) = (n+1)*(n+3)*(n+8)/6.at n=36A000297
- Numbers k such that k^2 is palindromic in base 7.at n=40A029992
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 66.at n=24A031564
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 66.at n=2A031744
- Base-7 palindromes that start with 4.at n=20A043018
- Number of solutions to n^2 < x^2 + y^2 + z^2 < (n+1)^2; number of lattice points between spheres of radii n and n+1.at n=28A078184
- Number of compositions of n into 6 parts such that no two adjacent parts are equal.at n=13A106355
- a(n) = (10^k - n)(10^k + n), where k is the number of digits in n.at n=13A110397
- Total sum of squares of number of distinct parts in all partitions of n.at n=20A135348
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (0, -1, 1), (1, -1, 0), (1, 1, -1), (1, 1, 0)}.at n=8A149351
- Number of binary strings of length n with equal numbers of 00000 and 01001 substrings.at n=14A164184
- a(n) = Sum_{j=1..prime(n)-1} floor(j^2/prime(n)).at n=39A165993
- n-th single or isolated number*n-th non-single or nonisolated number.at n=34A167885
- a(n) = largest number k such that k and k * n taken together have distinct digits, or 0 if no such k exists.at n=13A173780
- The number of equal-sized equilateral triangles in the highest stack of triangles contained in successive Genealodrons formed from 2^n - 1 same size equilateral triangles.at n=19A179316
- Triangle of coefficients of polynomials u(n,x) jointly generated with A210740; see the Formula section.at n=62A210739
- E.g.f. equals the series reversion of x - x*log(1+x).at n=5A227457
- a(n) is the minimal k such that nextprime(2k+1) - 2k = prime(n) where nextprime(n) is least prime > n.at n=15A229512
- Number of (n+1) X (7+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=10A253434
- Number of (7+1) X (n+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=10A253441