8065
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9684
- Proper Divisor Sum (Aliquot Sum)
- 1619
- 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
- 6448
- Möbius Function
- 1
- Radical
- 8065
- 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
- 70
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 55.at n=8A020394
- Numbers whose base-6 representation has exactly 6 runs.at n=25A043614
- Number of n X n matrices over GF(4) of order dividing 5 (i.e., number of solutions of X^5=I in GL(n,4)).at n=2A053860
- Triangle T(n,k) is the number of restricted growth strings (RGS) of set partitions of {1..n} that have a decrease at index k (1<=k<n).at n=35A056862
- Expansion of (1/2)*(exp(2*x)-1)*exp(exp(x)-1).at n=7A059606
- a(n) = (2*n-1)^2 + (2*n)^2.at n=31A060820
- a(n) = (prime(n)^2 + 1)/2.at n=29A066885
- a(n) = 8*n^2 - 4*n + 1.at n=32A080856
- Downward vertical of triangular spiral in A051682.at n=21A081272
- a(n) = 2^(2n+1) - 2^(n+1) + 1.at n=6A092440
- (Prime(prime(n))^2+1)/2.at n=10A092773
- a(n) = Sum_{k=0..floor(n/6)} C(n-3k,3k) * 2^k.at n=19A100135
- Least k such that prime(n)^2 divides binomial(2k,k).at n=30A110494
- Table of number of domino tilings of generalized Aztec pillows of type (1, ..., 1, 3, 1, ..., 1)_n.at n=27A112830
- Number of permutations of length n which avoid the patterns 1234, 2341, 4132.at n=9A116775
- a(n) = ceiling((2^n + 1 - 2*floor(2^(n/2)))/2).at n=13A129757
- a(n) = (n!+5)/5.at n=3A139152
- Triangle T(n,k), n>=1, 1<=k<=n, where the e.g.f. for column k satisfies: A_k(x) = exp(x*A_k(x^k/k!)).at n=38A143565
- E.g.f. satisfies A(x) = exp(x*A(x^3/3!)).at n=9A143567
- a(n) = 288*n + 1.at n=27A157990