1992
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
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 5040
- Proper Divisor Sum (Aliquot Sum)
- 3048
- 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
- 656
- Möbius Function
- 0
- Radical
- 498
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 50
- 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
- Number of P-equivalence classes of switching functions of n or fewer variables, divided by 2.at n=4A000612
- Number of cells of square lattice of edge 1/n inside quadrant of unit circle centered at 0.at n=50A001182
- Numbers k such that 33*2^k - 1 is prime.at n=28A002240
- Symmetries in planted 3-trees on n+1 vertices.at n=11A003611
- Oscillates under partition transform.at n=39A007213
- Coordination sequence T5 for Zeolite Code HEU.at n=29A008120
- Coordination sequence T2 for Zeolite Code LEV.at n=33A008128
- Coordination sequence T3 for Zeolite Code LIO.at n=31A008131
- Coordination sequence for 4-dimensional cubic lattice (points on surface of 4-dimensional cross-polytope).at n=9A008412
- Coordination sequence T5 for Zeolite Code -CLO.at n=40A009854
- a(n) = 12*a(n-1) + 11*a(n-2).at n=4A015612
- Seven iterations of Reverse and Add are needed to reach a palindrome.at n=27A015986
- a(n)-th squarefree is sum of first k squarefrees for some k.at n=38A020643
- Coordination sequence T2 for Zeolite Code IFR.at n=31A024983
- a(n) = T(2n-1,n), where T is the array in A026098.at n=22A026102
- Sequence satisfies T^2(a)=a, where T is defined below.at n=39A027596
- a(n) = binomial(n+2,2) + binomial(n+3,3) + binomial(n+4,4) + binomial(n+5,5).at n=8A027659
- The "semi-Fibonacci numbers": a(n) = A030067(2n - 1), where A030067 is the semi-Fibonacci sequence.at n=52A030068
- Every run of digits of n in base 7 has length 2.at n=34A033005
- Number of points of L1 norm 9 in cubic lattice Z^n.at n=4A035603