2569
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
- 2944
- Proper Divisor Sum (Aliquot Sum)
- 375
- 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
- 2196
- Möbius Function
- 1
- Radical
- 2569
- 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
- 53
- 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
- Coordination sequence T4 for Zeolite Code AET.at n=35A008010
- Coordination sequence T8 for Zeolite Code PAU.at n=37A008226
- Coordination sequence T1 for Zeolite Code -PAR.at n=36A009855
- [ n(n-1)(n-2)(n-3)/17 ].at n=16A011927
- Positive integers n such that 2^n == 2^7 (mod n).at n=56A015927
- Pseudoprimes to base 83.at n=29A020211
- Numbers k such that the continued fraction for sqrt(k) has period 72.at n=1A020411
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k=[ (n+1)/2 ], s = (natural numbers >= 2), t = (natural numbers >= 3).at n=27A024306
- a(n) = 2*(n+1) + 3*n + ... + (k+1)*(n+2-k), where k = floor(n/2).at n=27A024868
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = floor( n/2 ), s = natural numbers >= 2, t = natural numbers >= 3.at n=26A024869
- 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=21A026064
- Sequence satisfies T^2(a)=a, where T is defined below.at n=47A027589
- Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 15 (most significant digit on right and removing all least significant zeros before concatenation).at n=8A029532
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 30 ones.at n=10A031798
- "DGJ" (bracelet, element, labeled) transform of 1,2,3,4...at n=7A032224
- "EGJ" (unordered, element, labeled) transform of 1,2,3,4,...at n=7A032315
- Number of binary codes (not necessarily linear) of length n with 3 words.at n=41A034198
- Number of partitions of n with equal nonzero number of parts congruent to each of 0 and 3 (mod 4).at n=36A035548
- Number of partitions of n into parts not of the form 25k, 25k+9 or 25k-9. Also number of partitions with at most 8 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=27A036008
- Number of 4-ary rooted trees with n nodes and height at most 5.at n=13A036610