1995
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 3840
- Proper Divisor Sum (Aliquot Sum)
- 1845
- 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
- 864
- Möbius Function
- 1
- Radical
- 1995
- 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
- 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
- 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
- no
- Odd
- yes
Appears in sequences
- Powers of rooted tree enumerator.at n=6A000529
- Number of sublattices of index n in generic 3-dimensional lattice.at n=27A001001
- Odd squarefree numbers with an even number of prime factors that have no prime factors greater than 31.at n=49A002557
- Discriminants of the known imaginary quadratic fields with 1 class per genus (a finite sequence).at n=61A003644
- Expansion of hypergeom([3/2, 7/4, 2, 9/4], [7/3, 8/3, 3], (256/27)*x).at n=4A006633
- Coordination sequence T1 for Zeolite Code DDR.at n=28A008071
- Coordination sequence T2 for Cordierite.at n=27A008252
- Expansion of e.g.f.: cosh(x)*cos(log(1+x)).at n=7A009174
- Expansion of tan(tanh(x)/cos(x)).at n=3A009723
- a(n) = floor(n*(n-1)*(n-2)/4).at n=21A011886
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 3.at n=20A013591
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 4.at n=2A013592
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly three 1's.at n=29A013650
- a(n) = n*(9*n-2).at n=15A013656
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=11A015988
- Continued fraction for log(78).at n=45A016506
- Coordination sequence T1 for Zeolite Code CZP.at n=29A019456
- a(n) is the concatenation of n and 5n.at n=18A019553
- a(n) = n*(9*n + 1)/2.at n=21A022267
- a(n) = n*(11*n+1)/2.at n=19A022269