8045
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9660
- Proper Divisor Sum (Aliquot Sum)
- 1615
- 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
- 6432
- Möbius Function
- 1
- Radical
- 8045
- 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
- 44
- 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
- Number of numerical semigroups of genus n; conjecturally also the number of power sum bases for symmetric functions in n variables.at n=17A007323
- Number of admissible sequences of order j; related to 3x+1 problem and Wagon's constant.at n=12A100982
- Semiprimes (A001358) whose digit reversal is a powerful(1) number (A001694).at n=26A115688
- Each term k provides a value of (sum-of-digits of 5^k)/k that is closer to Pi than the previous value.at n=11A119666
- Numbers k such that binomial(4k, k) + 1 is prime.at n=25A125241
- Numbers k such that 2*k+1, 3*k+2 and 4*k+3 are primes.at n=36A126955
- Numbers n such that n^k+(n+1)^k is prime for k = 1, 2, 4.at n=43A128780
- Number of n X n binary arrays symmetric under 90-degree rotation with all ones connected only in two by two blocks.at n=13A145863
- Positive numbers y such that y^2 is of the form x^2+(x+89)^2 with integer x.at n=9A160055
- Total area of the largest inscribed rectangles of all integer partitions of n.at n=20A182099
- Length of Collatz dropping time patterns in A186008.at n=13A186009
- Numerator of the frequency of the n-th dropping time in the Collatz iteration.at n=13A186107
- a(n) is the number of odd numbers k < 2^n such that A260590(k) = n.at n=20A260591
- Self-composition of the Pell numbers; g.f.: A(x) = G(G(x)), where G(x) = g.f. of A000129.at n=7A279285
- Expansion of Product_{k>=2} 1/(1 - x^k)^omega(k), where omega(k) is the number of distinct primes dividing k (A001221).at n=37A293548
- Total number of parts in all symmetric m-color cyclic compositions of n (that is, the total number of parts in all achiral cyclic compositions of n where a part with size m can be colored with one of m colors).at n=12A307415
- Irregular triangle T(n,k) read by rows: similar to A009766 but length of rows grows like log(3)/log(2).at n=67A368514