2618
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 5184
- Proper Divisor Sum (Aliquot Sum)
- 2566
- 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
- 960
- Möbius Function
- 1
- Radical
- 2618
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 146
- 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
- Exponentiation of g.f. for rooted trees.at n=6A006871
- Shifts 4 places right under inverse binomial transform.at n=11A010748
- a(n) = floor(n*(n-1)*(n-2)/15).at n=35A011897
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 3.at n=30A013591
- Expansion of 1/(1-x^2-x^3-x^4-x^5-x^6).at n=20A013983
- Expansion of 1/((1-x)(1-4x)(1-5x)(1-9x)).at n=3A021772
- Fibonacci sequence beginning 2, 10.at n=13A022367
- Least term in period of continued fraction for sqrt(n) is 6.at n=18A031430
- Quotient of 'base-24' division described in A032579.at n=55A032580
- Coordination sequence T2 for Zeolite Code CFI.at n=34A033600
- Numbers n such that BCR(n) = n, where BCR = binary-complement-and-reverse = take one's complement then reverse bit order.at n=39A035928
- Number of pairs {i,j}, i>1, j>1, such that ij < n^2.at n=30A037048
- Coordination sequence T4 for Zeolite Code ESV.at n=34A038411
- Numbers k such that k-th and (k+1)-st term of A038593 differ by 2.at n=47A038633
- Numbers k such that the string 2,8 occurs in the base 9 representation of k but not of k-1.at n=36A044277
- Numbers n such that string 1,8 occurs in the base 10 representation of n but not of n-1.at n=29A044350
- Numbers n such that string 2,8 occurs in the base 9 representation of n but not of n+1.at n=36A044658
- Numbers n such that string 5,2 occurs in the base 9 representation of n but not of n+1.at n=35A044679
- Numbers n such that string 1,8 occurs in the base 10 representation of n but not of n+1.at n=29A044731
- Numbers whose base-4 representation contains exactly one 0 and four 2's.at n=26A045046