6847
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7056
- Proper Divisor Sum (Aliquot Sum)
- 209
- 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
- 6640
- Möbius Function
- 1
- Radical
- 6847
- Omega Function (Ω)
- 2
- 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
- 62
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Spiral sieve using Fibonacci numbers.at n=18A005620
- Crystal ball sequence for hexagonal close-packing.at n=12A007202
- a(0) = 1, a(n) = 5*n^2 + 2 for n>0.at n=37A010001
- Numbers k such that the continued fraction for sqrt(k) has period 80.at n=22A020419
- a(n) = T(2n-1,n), where T is the array in A026098.at n=38A026102
- Partial sums of A005001.at n=8A029761
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 81.at n=22A031579
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 38 ones.at n=41A031806
- Second 10-gonal (or decagonal) numbers: n*(4*n+3).at n=41A033954
- Numerators of continued fraction convergents to sqrt(611).at n=8A042172
- Numbers whose base-4 representation contains exactly three 2's and three 3's.at n=20A045151
- A Diaconis-Mosteller approximation to the Birthday problem function.at n=32A050255
- "Stirling-Bernoulli transform" of Fibonacci numbers.at n=7A050946
- Expansion of g.f. (1-sqrt(1-4*x-4*x^2))/(2*(1+x)).at n=9A052709
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 83 ).at n=24A063356
- Triangle T(n,k) (n>=0, 0 <= k <= n) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using only steps R=(1,0), V=(0,1) and D=(1,2).at n=44A071943
- Triangle T(n,k) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using steps R=(1,0), V=(0,1) and D=(2,1).at n=43A071945
- Triangle T(n,k) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using steps R=(1,0), V=(0,1) and D=(2,1).at n=44A071945
- Triangle of numbers relating two simple context-free grammars (A052709 and A052705).at n=36A073152
- Smallest multiple of (n+1)-st prime which is == 1 mod n-th prime.at n=37A073604