9823
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 11520
- Proper Divisor Sum (Aliquot Sum)
- 1697
- 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
- 8280
- Möbius Function
- -1
- Radical
- 9823
- 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
- 122
- 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
- Number of centered trees with n nodes.at n=16A000676
- a(n) = Sum_{k=0..n} (k+1) * A026758(n, k).at n=10A027235
- Least term in period of continued fraction for sqrt(n) is 9.at n=12A031433
- Smallest value of x such that M(x) = -n, where M(x) is Mertens's function A002321.at n=37A051401
- Inverse Mertens function: smallest k such that |M(k)| = n, where M(x) is Mertens's function A002321.at n=37A051402
- Indices of primes in sequence defined by A(0) = 33, A(n) = 10*A(n-1) - 17 for n > 0.at n=8A056251
- An inverse to Mertens's function: smallest k >= 2 such that Mertens's function |M(k)| (see A002321) is equal to n.at n=38A060434
- Difference between 2^n and the next smaller or equal power of 3.at n=14A063005
- Odd interprimes divisible by 19.at n=25A126231
- Main diagonal of array A[k,n] = n-th sum of 3 consecutive k-gonal numbers, k>2.at n=18A130423
- Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct and not zero, and Sum_{i=1..k-1} d_i^i = d_k^k.at n=5A169738
- a(n) = 81*n^2 + 2*n.at n=10A177099
- Base 10 numbers d_1 d_2 ... d_k such that the digits d_i are distinct, and Sum_{i=1..k-1} d_i^i = d_k^k.at n=7A177772
- Monotonic ordering of nonnegative differences 2^i-9^j, for 40>=i>=0, j>=0.at n=36A192122
- Monotonic ordering of nonnegative differences 4^i-3^j, for 40>=i>=0, j>=0.at n=31A192148
- Monotonic ordering of nonnegative differences 4^i-9^j, for 40>= i>=0, j>=0.at n=18A192169
- Numbers n such that 4n+1 is a palindromic prime.at n=32A192261
- Number of subsets of {1,...,n} containing {a,a+2,a+4} for some a.at n=14A209409
- Number of partitions of n+7 with largest inscribed rectangle having area <= n.at n=26A218628
- Composite squarefree numbers n such that p(i)-5 divides n+5, where p(i) are the prime factors of n.at n=10A225705