2182
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3276
- Proper Divisor Sum (Aliquot Sum)
- 1094
- 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
- 1090
- Möbius Function
- 1
- Radical
- 2182
- 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
- 45
- Smith Number
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- Number of degree-n irreducible polynomials over GF(2); number of n-bead necklaces with beads of 2 colors when turning over is not allowed and with primitive period n; number of binary Lyndon words of length n.at n=15A001037
- Number of 3-connected nets with n edges.at n=12A002880
- Coordination sequence T4 for Zeolite Code MEL.at n=30A008153
- a(n) = floor(n*(n-1)*(n-2)/15).at n=33A011897
- Numbers k such that the continued fraction for sqrt(k) has period 38.at n=16A020377
- Ordered sequence of distinct terms of the form floor(x^i * floor(x^j)), i,j >= 0, where x = sqrt(3).at n=33A022769
- Number of products of distinct primes <= prime(n) equal to -1 (mod prime(n)).at n=17A024404
- Every prefix prime in base 9 (written in base 9).at n=26A024769
- Coordination sequence T3 for Zeolite Code IFR.at n=33A024984
- [ Sum (s(j) - s(i))^2 ], 1 <= i < j <= n, where s(k) = 1 + 1/2 + ... + 1/k.at n=54A025216
- Number of 4-balanced strings of length n: let d(S)= #(1)'s in S - #(0)'s, then S is k-balanced if every substring T has -k<=d(T)<=k; here k=4.at n=12A027559
- 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 46.at n=5A031544
- a(n) = floor(10000/sqrt(n)).at n=20A033433
- Zeckendorf expansion of n: repeatedly subtract the largest Fibonacci number you can until nothing remains. Big-endian concatenation of decimals.at n=31A035514
- Numbers n such that digit sum of n equals digit sum of 'juxtaposition' and 'sum' of its prime factors (counted with multiplicity).at n=40A036921
- Digit sum of 'even' number equals digit sum of 'sum' and 'juxtaposition' of its prime factors (counted with multiplicity).at n=23A036926
- Product_{k>=1}1/(1 - x^k)^a(k) = 1 + 2x.at n=14A038063
- Product_{k>=1} (1 + x^k)^a(k) = 1 + 2x.at n=14A038067
- a(n)=(s(n)+8)/10, where s(n)=n-th base 10 palindrome that starts with 2.at n=40A043081
- Numbers n such that string 0,6 occurs in the base 8 representation of n but not of n-1.at n=37A044193