2823
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3768
- Proper Divisor Sum (Aliquot Sum)
- 945
- 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
- 1880
- Möbius Function
- 1
- Radical
- 2823
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 58
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Coordination sequence T3 for Zeolite Code MEL.at n=34A008152
- Coordination sequence T1 for Zeolite Code MTW.at n=35A008196
- Expansion of Product_{m>=1} (1 + m*q^m)^12.at n=4A022640
- a(n) = p(1)p(n) + p(2)p(n-1) + ... + p(k)p(n-k+1), where k = [ n/2 ], p = A000040, the primes.at n=16A025129
- a(n) = T(2n-1,n-2), T given by A026648.at n=5A026653
- Number of polyhexes of class PF2 with a particular symmetry.at n=12A030525
- 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 17.at n=23A031515
- Number of partitions in parts not of the form 11k, 11k+3 or 11k-3. Also number of partitions with at most 2 parts of size 1 and differences between parts at distance 4 are greater than 1.at n=32A035946
- Numbers k such that the string 7,6 occurs in the base 9 representation of k but not of k-1.at n=38A044320
- Numbers n such that string 2,3 occurs in the base 10 representation of n but not of n-1.at n=31A044355
- Numbers n such that string 7,6 occurs in the base 9 representation of n but not of n+1.at n=38A044701
- Numbers n such that string 2,3 occurs in the base 10 representation of n but not of n+1.at n=31A044736
- a(n) = T(2n-1,n), array T given by A048201.at n=27A048208
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 22.at n=28A051987
- Numbers k such that k^10 == 1 (mod 11^3).at n=22A056085
- Least k such that k*10^n +/- 1 are twin primes.at n=44A064218
- Numbers n such that f(n) and f(f(n)) are prime, where f(k) = decimal encoding of the prime factorization of k.at n=39A067600
- a(n) = sum_{k=1..n} prime(k)*prime(k+1).at n=9A074745
- Numbers k such that p=k^2+2 and p+2 are primes.at n=33A086381
- Bisection of A088567.at n=40A088585