8015
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 11040
- Proper Divisor Sum (Aliquot Sum)
- 3025
- 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
- 5472
- Möbius Function
- -1
- Radical
- 8015
- 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
- 44
- 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 solutions to c(1)*prime(1) + ... + c(n)*prime(n) = 1, where c(i) = +-1 for i > 1, c(1) = 1.at n=21A022895
- a(n) = (d(n)-r(n))/2, where d = A026063 and r is the periodic sequence with fundamental period (1,1,0,1).at n=35A026064
- Numbers whose base-6 representation has exactly 6 runs.at n=14A043614
- a(n)=T(2n-1,n), array T given by A048212.at n=46A048221
- Triangle T = A007318*A271703; T(n,m)= Sum_{i=0..n} L'(n,i)*binomial(i,m), m=0..n.at n=32A059110
- The minimal number which has multiplicative persistence 8 in base n.at n=11A064872
- a(1) = 1, a(n) = a(n - 1) + pi(a(n - 1)) + 1.at n=38A065962
- a(n)=Sum_{j = 0..n} binomial(phi(n),phi(j)).at n=27A073317
- Least nontrivial multiple of the n-th prime beginning with 8.at n=49A078292
- Coefficients of x^n in the n-th iteration of x/(1-x)^2 for n>=1.at n=4A119821
- Smaller side not divisible by 37 of right triangles with integer sides and integer side inscribed squares with two vertices on the hypotenuse.at n=9A123697
- Triangle read by rows: T(n,k) is the number of set partitions of the set {1,2,...,n} (or of any n-set) containing k blocks of size 3 (0<=k<=floor(n/3)).at n=18A124503
- Number of partitions of an n-set without blocks of size 3.at n=9A124504
- Number of length 3 0..n arrays with each partial sum starting from the beginning no more than sqrt(3) standard deviations from its mean.at n=19A244942
- Number of integers in n-th generation of tree T(-2/3) defined in Comments.at n=32A274150
- Number of nX3 0..1 arrays with every element equal to 0, 1, 2 or 4 king-move adjacent elements, with upper left element zero.at n=15A297884
- Number of 4Xn 0..1 arrays with every element equal to 0, 1 or 4 horizontally or antidiagonally adjacent elements, with upper left element zero.at n=10A301966
- a(n) is the greatest nonnegative number which has a partition into a triangular number (A000217), a square number (A000290), and a pentagonal number (A000326) in n different ways.at n=32A327792
- T(n, k) = Sum_{m = 0..n-1} Stirling1(m+1, k)*binomial(n, m)*(-1)^(n + k), where "Stirling1" are the signed Stirling numbers of the first kind.at n=22A367198
- Maximal coefficient of (1 + x^3) * (1 + x^5) * (1 + x^7) * ... * (1 + x^prime(n)).at n=22A369708