2973
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
- 5
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3968
- Proper Divisor Sum (Aliquot Sum)
- 995
- 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
- 1980
- Möbius Function
- 1
- Radical
- 2973
- 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
- 97
- 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
- Number of irreducible indecomposable spherical curves with n crossings (only ordinary double points), the circle is oriented, the sphere is not oriented (OU case).at n=10A007756
- Coordination sequence T7 for Zeolite Code EUO.at n=34A008102
- Coordination sequence for sigma-CrFe, Position Xd.at n=14A009959
- Expansion of 1/(1-x^3-x^4-x^5-x^6-x^7-x^8-x^9).at n=26A017822
- Numbers k such that the continued fraction for sqrt(k) has period 50.at n=10A020389
- Numbers k such that Fibonacci(k) == 2 (mod k).at n=46A023174
- a(n) = Sum_{0<=j<=i<=n} A027113(i, n+j).at n=7A027130
- 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 36.at n=14A031534
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 22 ones.at n=36A031790
- Decimal part of a(n)^(1/n) starts with a 'nine digits' anagram.at n=34A035136
- Numerators of continued fraction convergents to sqrt(548).at n=5A042048
- Numbers k such that the string 6,3 occurs in the base 9 representation of k but not of k-1.at n=40A044308
- Numbers n such that string 7,3 occurs in the base 10 representation of n but not of n-1.at n=32A044405
- Numbers n such that string 7,3 occurs in the base 10 representation of n but not of n+1.at n=32A044786
- Numbers whose base-5 representation contains exactly three 3's and two 4's.at n=7A045306
- Numbers with multiplicative persistence value 5.at n=36A046514
- List of binary palindromes of even length (written in base 10).at n=46A048701
- Numbers n such that prime(n) - sigma(n) - phi(n) = prime(n+1) - sigma(n+1) - phi(n+1), where sigma(n) = sum of divisors of n.at n=26A048783
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 18.at n=26A050967
- a(n) = a(n-1) + a(n-1 minus the number of terms of the same parity as n so far).at n=41A060714