2817
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 4082
- Proper Divisor Sum (Aliquot Sum)
- 1265
- 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
- 1872
- Möbius Function
- 0
- Radical
- 939
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 2
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
- 84
- 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
- no
- Odd
- yes
Appears in sequences
- a(0) = 1, a(1) = 4, and a(n) = a(n-1) + a(n-2) for n >= 2.at n=15A000285
- Sum of 12 nonzero 8th powers.at n=11A003390
- Reve's puzzle: number of moves needed to solve the Towers of Hanoi puzzle with 4 pegs and n disks, according to the Frame-Stewart algorithm.at n=40A007664
- Coordination sequence T7 for Zeolite Code EUO.at n=33A008102
- Coordination sequence T5 for Zeolite Code MFS.at n=33A008177
- Coordination sequence T2 for Coesite.at n=28A008268
- Coordination sequence T3 for Zeolite Code -CHI.at n=34A009848
- Coordination sequence T1 for Zeolite Code RUT.at n=35A009897
- Number of 5-tuples of different integers from [ 1,n ] with no common factors among pairs.at n=24A015698
- Number of 2's in n-th term of A022470.at n=31A022473
- Partial sums of the sequence of prime powers (A000961).at n=47A024918
- a(n) = T(n,n-3), where T is the array in A026374.at n=16A026382
- a(n) = T(n,n-3), where T is the array in A026386.at n=16A026394
- Numbers k such that k divides the (right) concatenation of all numbers <= k written in base 25 (most significant digit on right).at n=16A029518
- Numbers k such that 129*2^k+1 is prime.at n=13A032414
- Numbers whose set of base-7 digits is {1,3}.at n=33A032914
- Multiplicity of highest weight (or singular) vectors associated with character chi_3 of Monster module.at n=46A034391
- Concatenations C1 and C2 are both prime (see the comment lines).at n=38A034816
- a(n) is the number of numbers k with 2^(n-1) < k <= 2^n having a number of divisors that is a power of 2.at n=12A036539
- Partial sums of Fibonacci-lucky numbers.at n=47A039677