9842
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 18240
- Proper Divisor Sum (Aliquot Sum)
- 8398
- 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
- 3888
- Möbius Function
- 1
- Radical
- 9842
- Omega Function (Ω)
- 4
- 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
- 73
- 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
- a(n) = (n-1)*n*(n+4)/6.at n=38A005581
- a(n) = (3^n + 1)/2.at n=9A007051
- Degree of variety K_{2,n}^2.at n=3A013699
- Number of words of length n (n >= 1) over a two-letter alphabet having a minimal period of size n-1.at n=14A019310
- Plaindromes: numbers whose digits in base 3 are in nondecreasing order.at n=46A023745
- Expansion of 1/((1-5x)(1-6x)(1-9x)(1-11x)).at n=3A028175
- Positive numbers k such that (k+1)*(k+2)*(k+3)*(k+4)/(k+(k+1)+(k+2)+(k+3)+(k+4)) is an integer.at n=20A032795
- a(n) = ceiling((n^3)/2).at n=27A036486
- Numbers whose base-3 representation contains no 0's and exactly one 2.at n=36A044990
- Array A read by diagonals; n-th difference of (A(k,n), A(k,n-1),..., A(k,0)) is (k+2)^(n-1), for n=1,2,3,...; k=0,1,2,...at n=45A047848
- Array T read by diagonals: T(k,n) = 2^(k-1) * (3^n - 1) + 1.at n=45A048471
- Thickened cube numbers: a(n) = n*(n^2 + (n-1)^2) + (n-1)*2*n*(n-1).at n=13A050492
- Number of periodic palindromic structures of length n using a maximum of three different symbols.at n=19A056504
- McKay-Thompson series of class 18a for Monster.at n=54A058536
- McKay-Thompson series of class 18d for the Monster group.at n=18A058539
- Third step in Goodstein sequences, i.e., g(5) if g(2)=n: write g(4)=A057650(n) in hereditary representation base 4, bump to base 5, then subtract 1 to produce g(5).at n=7A059934
- Numbers k such that k and its reversal are both multiples of 19.at n=30A062907
- Non-palindromic number and its reversal are both multiples of 19.at n=20A062916
- Triangle where T(n,k)=2*T(n,k-1)+C(n-1,k)-C(n-1,k-1) and n>=k>=0.at n=64A067337
- The terms of A055235 (sums of two powers of 3) divided by 2.at n=45A073216