5538
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 12096
- Proper Divisor Sum (Aliquot Sum)
- 6558
- 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
- 1680
- Möbius Function
- 1
- Radical
- 5538
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 67
- 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
- Number of n-step self-avoiding walks on hexagonal lattice from (0,0) to (1,1).at n=7A003291
- Coordination sequence for sigma-CrFe, Position Xb.at n=19A009960
- Probable extension of A013704.at n=15A025495
- a(n) = T(n,n-4), T given by A026536. Also a(n) = number of integer strings s(0), ..., s(n), counted by T, such that s(n) = 4.at n=9A026541
- Numbers having period-1 7-digitized sequences.at n=32A031201
- Number of necklaces with 7 black beads and n-7 white beads.at n=14A032192
- Numbers m such that m^2 ends in 444.at n=22A039685
- a(n) = (6*n^4 + 30*n^3 - 20*n^2 + 14)*n/30 + (n mod 2).at n=7A064837
- Least positive integer multiples of angle x such that their direction cosines form a unit vector: Sum_{k>0} cos(a(k)*x)^2 = 1, where a(1)=1, a(n+1)>a(n) and x=5/4.at n=31A080198
- a(n) = (1/(3*n))*Sum_{d|n, d even} phi(2*n/d)*binomial(3d/2,d).at n=7A082936
- a(n)=floor{square((1*n^0+1*n^1+2*n^2+4*n^3)/(1*n^0+2*n^1+1*n^2))}.at n=19A086863
- Number of single nodes (exactly one node on that level) for all Motzkin paths of length n.at n=12A088457
- a(n) is the smallest natural number m such that n^m + m is prime.at n=25A093324
- 0*9, 1*8, 2*7, 3*6, 4*5; 10*19, 11*18, ..., 14*15; 20*29, 21*28, ..., 24*25; 30*39, ...at n=36A096229
- Numbers n for which 8*R_n - 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=15A096846
- a(n)=the sum of the (1,2)- and (1,3)-entries and twice the (1,4)-entry of the matrix P^n + T^n, where the 4 X 4 matrices P and T are defined by P=[0,1,0,0;0,0,1,0;0,0,0,1;1,0,0,0] and T=[0,1,0,0;0,0,1,0;0,0,0,1;1,1,1,1].at n=15A109525
- a(n) = n*(8*n+5).at n=26A139277
- a(n) is the minimal values of A007947((2^n)*m*(2^n-m)).at n=15A143702
- Numbers k such that the string k modulo 1000 is found at position k in the decimal digits of Pi.at n=17A153226
- a(n) = Sum_{k=0..n} A109613(k)*A005843(n-k).at n=25A171218