2085
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3360
- Proper Divisor Sum (Aliquot Sum)
- 1275
- 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
- 1104
- Möbius Function
- -1
- Radical
- 2085
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 125
- 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
- Expansion of a modular function for Gamma_0(15).at n=13A002510
- a(n) = ceiling(n*phi^13), where phi is the golden ratio, A001622.at n=4A004968
- Coordination sequence T1 for Zeolite Code CHA.at n=35A008066
- Number of ordered quadruples of integers from [ 1,n ] with no common factors between triples.at n=15A015635
- Conjectured formula for irreducible 5-fold Euler sums of weight 2n+13.at n=25A019450
- a(n) = sum of the numbers between the two n's in A026370.at n=23A026373
- Lucky numbers with size of gaps equal to 10 (lower terms).at n=22A031892
- Number of ways to partition n elements into pie slices of different sizes of at least 2 allowing the pie to be turned over.at n=34A032230
- a(n) = floor(10000/sqrt(n)).at n=22A033433
- Grundy function for turn-at-most-4-coins game.at n=40A033623
- Numbers having three 3's in base 6.at n=35A043383
- Numbers k such that string 3,6 occurs in the base 7 representation of k but not of k-1.at n=48A044165
- Numbers k such that string 4,5 occurs in the base 8 representation of k but not of k-1.at n=36A044224
- Numbers k such that the string 6,6 occurs in the base 9 representation of k but not of k-1.at n=25A044311
- Numbers n such that string 8,5 occurs in the base 10 representation of n but not of n-1.at n=22A044417
- Numbers n such that string 4,5 occurs in the base 8 representation of n but not of n+1.at n=36A044605
- Numbers n such that string 6,6 occurs in the base 9 representation of n but not of n+1.at n=25A044692
- Numbers n such that string 8,5 occurs in the base 10 representation of n but not of n+1.at n=22A044798
- Sum{T(i,n-i): i=0,1,...,n}, array T as in A047120.at n=12A047121
- Starting positions of strings of 2 4's in the decimal expansion of Pi.at n=16A050230