8789
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 32
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 10368
- Proper Divisor Sum (Aliquot Sum)
- 1579
- 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
- 7360
- Möbius Function
- -1
- Radical
- 8789
- 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
- 96
- 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
- a(n) = (1/2)*(1 + Sum_{k=0..n} binomial(2*k, k)).at n=8A024718
- Least m such that if r and s in {1/1, 1/4, 1/9,..., 1/n^2} satisfy r < s, then r < k/m < s for some integer k.at n=28A024827
- Shortest edge c of (measured by the longest edge) primitive Euler bricks (a, b, c, sqrt(a^2 + b^2), sqrt(b^2 + c^2), sqrt(a^2 + c^2) are integers).at n=26A031175
- Every run of digits of n in base 16 has length 2.at n=34A033014
- Number of partitions of n into parts 4k+1 and 4k+2 with at least one part of each type.at n=52A035624
- Positive integers having more base-16 runs of even length than odd.at n=36A044842
- Sum of digits = 8 times number of digits.at n=25A061425
- Sides of integer Heronian triangles [A068967(n), prime(A068967(n)), a(n)] with area A068969(n).at n=17A068968
- a(n) = Sum_{k=0..n} (-1)^(n-k)*binomial(k,floor(k/2)).at n=16A086905
- a(n) = number of Egyptian fractions 1 = 1/x_1 + ... + 1/x_k (for any k), 0<x_1<...<x_k=n.at n=51A092669
- Nonzero elements of A092669.at n=16A092672
- Fourth column of (1,5)-Pascal triangle A096940.at n=32A096941
- Triangle T(n,k) read by rows: number of lattice paths from (0,0) to (0,2n) with steps (1,1) or (1,-1) that stay between the lines y=0 and y=k.at n=37A101475
- Start to read the sequence digit by digit and erase the first "1" you encounter, then the first "2", the first "3", etc., until the first "9"; go on from there and erase again the first "1", the first "2", etc., until "9" -- and so on, cyclically until the end of the (infinite) sequence. Concatenate what is left. The result is the concatenation of all integers of the sequence.at n=10A108709
- Beginning with 3, least number such that concatenation of first n terms and its digit reversal both are primes.at n=18A111382
- Antidiagonal sums of A096465.at n=16A124642
- Right-angled numbers with an internal digit as the vertex.at n=45A135602
- Numerator of Euler(n, 2/21).at n=3A156777
- a(n) = 4*n^2 + 79*n + 390.at n=36A157434
- a(n) = 338*n + 1.at n=25A158000