5269
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5760
- Proper Divisor Sum (Aliquot Sum)
- 491
- 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
- 4780
- Möbius Function
- 1
- Radical
- 5269
- 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
- 54
- Smith Number
- yes
- 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
- Erroneous version of A002572.at n=17A001180
- Number of partitions of 1 into n powers of 1/2; or (according to one definition of "binary") the number of binary rooted trees.at n=17A002572
- Number of trees with stability index n.at n=10A003429
- a(n) = a(n-1) + a(n-2) + F(n) - 1, a(0) = a(1) = 0, where F() = Fibonacci numbers A000045.at n=15A006478
- Wolstenholme numbers: numerator of Sum_{k=1..n} 1/k^2.at n=4A007406
- Coordination sequence T1 for Zeolite Code TON.at n=45A008241
- Number of (unordered) triples of integers from [1,n] with no common factors between pairs.at n=46A015617
- Numbers n such that phi(n + 1) | sigma(n) for n congruent to 1 (mod 3).at n=19A015817
- Squarefree n such that Q(sqrt(n)) has class number 5.at n=40A029705
- Decimal part of cube root of a(n) starts with 4: first term of runs.at n=16A034130
- Numerators of continued fraction convergents to sqrt(829).at n=6A042600
- Numbers whose base-2 representation has exactly 11 runs.at n=23A043578
- a(n) = (1/2)*(n-th number whose base-2 representation has exactly 12 runs).at n=25A043686
- Numbers n such that number of runs in the base 2 representation of n is congruent to 1 mod 10.at n=35A043764
- Starting positions of strings of 2 3's in the decimal expansion of Pi.at n=40A050222
- Numbers n such that n | 9^n + 8^n + 7^n + 6^n + 5^n + 4^n + 3^n + 2^n.at n=7A057284
- Number of parts if 3^n is partitioned into parts of size 2^n as far as possible and into parts of size 1^n.at n=12A060692
- Numbers k such that phi((prime(k)-1)/2) = sigma(k).at n=27A068474
- Rounded total surface area of a regular octahedron with edge length n.at n=39A071396
- a(n) = A077211(n)^(1/2).at n=10A077212