7266
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
- 16704
- Proper Divisor Sum (Aliquot Sum)
- 9438
- 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
- 2064
- Möbius Function
- 1
- Radical
- 7266
- 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
- 70
- 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
- Second-order Euler numbers.at n=6A002435
- Representation degeneracies for boson strings.at n=30A005292
- Triangle of coefficients in expansion of D^n (sec x) / sec x in powers of tan x.at n=17A008294
- Expansion of e.g.f.: sinh(log(1+x)/cos(x)).at n=7A009582
- Expansion of 1/((1-x)*(1-6*x)*(1-9*x)*(1-11*x)).at n=3A024346
- a(n) = T(2n-1,n), where T is the array in A026098.at n=39A026102
- Numbers k such that 133*2^k+1 is prime.at n=18A032416
- Convolution of Catalan numbers A000108 with A020918.at n=4A045724
- Number of edges in all noncrossing connected graphs on n nodes on a circle.at n=4A045741
- Triangle related to A001700 and A000302 (powers of 4).at n=31A046658
- Starting from generation 6 add previous and next term yielding generation 7.at n=28A048453
- a(n+4) = floor( ( a(n) + 2*a(n+1) + 3*a(n+2) + 4*a(n+3) )/5 ), with a(0), a(1), a(2), a(3) equal to 0, 1, 2, 3.at n=24A074733
- Non-balanced numbers in A015765.at n=32A074868
- Sum of primitive roots of n-th prime.at n=39A088144
- a(n) = K_4(n) = Sum_{k>=0} A090285(4,k)*2^k*binomial(n,k). a(n) = 2*(n^4+14*n^3+62*n^2+91*n+21)/3.at n=7A090296
- Triangle T(n,k), 0 <= k <= n, read by rows, defined by T(0,0) = 1; T(0,k) = 0 if k>0 or if k<0; T(n,k) = k*T(n-1,k-1) + (k+1)*T(n-1,k+1).at n=31A104035
- Triangular array formed by the Mersenne numbers.at n=50A110441
- Riordan array (1/(1+3x+2x^2),x/(1+3x+2x^2)).at n=50A111806
- Numbers n such that p(10n) is prime, where p(n) is the number of partitions of n.at n=15A114170
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, -1, 1), (-1, 0, 1), (1, 0, -1), (1, 1, 0)}.at n=8A149148