2166
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
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 4572
- Proper Divisor Sum (Aliquot Sum)
- 2406
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 684
- Möbius Function
- 0
- Radical
- 114
- Omega Function (Ω)
- 4
- 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
- 138
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Coordination sequence T2 for Zeolite Code MOR.at n=30A008183
- Expansion of (1+x^9)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=53A008770
- Coordination sequence T3 for Zeolite Code -ROG.at n=35A009861
- Triangle of numbers arising from analysis of Levine's sequence A011784.at n=55A014621
- Numbers k that divide s(k), where s(1)=1, s(j)=18*s(j-1)+j.at n=40A014868
- Self-convolution of natural numbers >= 3.at n=18A023551
- Convolution of A001950 and A014306.at n=43A023669
- Numbers that are the sum of 3 distinct nonzero squares in exactly 9 ways.at n=40A025347
- a(n) = n^2 + n + 4.at n=46A027689
- 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=2A031544
- Concentric hexagonal numbers: floor(3*n^2/2).at n=38A032528
- a(n) = 6*n^2.at n=19A033581
- Successive approximations to 7-adic integer sqrt(2).at n=4A034945
- Number of partitions in parts not of the form 15k, 15k+1 or 15k-1. Also number of partitions with no part of size 1 and differences between parts at distance 6 are greater than 1.at n=34A035955
- a(n) = (s(n)+1)/7, where s(n) = n-th base 7 palindrome that starts with 6.at n=31A043064
- Numbers k such that string 6,6 occurs in the base 8 representation of k but not of k-1.at n=33A044241
- Numbers k such that the string 6,6 occurs in the base 9 representation of k but not of k-1.at n=26A044311
- Numbers n such that string 6,6 occurs in the base 10 representation of n but not of n-1.at n=21A044398
- Numbers n such that string 6,6 occurs in the base 8 representation of n but not of n+1.at n=33A044622
- Numbers n such that string 6,6 occurs in the base 9 representation of n but not of n+1.at n=26A044692