2015
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 2688
- Proper Divisor Sum (Aliquot Sum)
- 673
- 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
- 1440
- Möbius Function
- -1
- Radical
- 2015
- Omega Function (Ω)
- 3
- 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
- 94
- 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
- Number of trees of diameter 5.at n=17A000147
- Number of sublattices of index n in generic 3-dimensional lattice.at n=23A001001
- Expansion of 1/((1-x)^2*(1-x^2)*(1-x^5)).at n=45A001304
- Numbers k such that 4!*(2k-5)!/(k!*(k-1)!) is an integer.at n=14A004784
- 5!(2n-6)!/n!(n-1)! is an integer.at n=19A004785
- Lucas-Carmichael numbers: squarefree composite numbers k such that p | k => p+1 | k+1.at n=2A006972
- Coordination sequence T1 for Zeolite Code DAC.at n=28A008067
- Coordination sequence T4 for Zeolite Code EMT.at n=37A008089
- Coordination sequence T1 for Zeolite Code SGT.at n=28A008229
- Coordination sequence T2 for Keatite.at n=25A009845
- a(n) = n*(2*n + 3).at n=31A014106
- Numbers whose base-4 representation is the juxtaposition of two identical strings.at n=30A020332
- Numbers whose base-8 representation is the juxtaposition of two identical strings.at n=30A020336
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (odd natural numbers), t = A001950 (upper Wythoff sequence).at n=15A025114
- Number of positive integers that are not the sum of distinct n-th-order polygonal numbers.at n=22A025524
- T(n,1) + T(n,2) + ... T(n,n), where T is the array in A026098.at n=14A026101
- Binary expansion contains a single 0.at n=50A030130
- Numbers k such that the continued fraction for sqrt(k) has even period 2*m and the m-th term of the periodic part is 7.at n=30A031410
- Numbers whose base-4 representation has 4 fewer 0's than 3's.at n=15A031469
- Numbers each of whose runs of digits in base 12 has length 2.at n=21A033010