6526
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 10584
- Proper Divisor Sum (Aliquot Sum)
- 4058
- 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
- 3000
- Möbius Function
- -1
- Radical
- 6526
- 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
- 75
- 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
- yes
- Odd
- no
Appears in sequences
- Length of one version of Kolakoski sequence {A000002(i)} at n-th growth stage.at n=22A001083
- Coordination sequence T1 for Coesite.at n=43A008267
- Coordination sequence for FeS2-Pyrite, S position.at n=39A009956
- a(n) = Sum_{j=1..n} j*prime(j).at n=17A014285
- Numbers k such that k | 10^k + 10.at n=17A015902
- Numbers k such that the continued fraction for sqrt(k) has period 90.at n=7A020429
- Least m such that if r and s in {1/1, 1/3, 1/6,..., 1/C(n+1,2)} satisfy r < s, then r < k/m < s for some integer k.at n=32A024826
- Expansion of 1/((1-2x)(1-4x)(1-9x)(1-11x)).at n=3A025981
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 38 ones.at n=34A031806
- Number of partitions satisfying (cn(0,5) = 0 and cn(2,5) = cn(3,5)).at n=47A036815
- Numbers n such that there are equal numbers of 0's and 1's in first n digits of binary representation of Pi.at n=27A039624
- 22-gonal numbers: a(n) = n*(10*n-9).at n=26A051874
- Numbers k such that k^18 == 1 (mod 19^3).at n=16A056089
- Integer part of (Product(n^((1 + log(i))/i^2), {i, 1, n})).at n=37A062482
- Nearest integer to (Product(n^((1 + log(i))/i^2), {i, 1, n})).at n=37A062483
- Maximal value of Sum_{i=1..n} (p(i) - p(i+1))^2, where p(n+1) = p(1), as p ranges over all permutations of {1, 2, ..., n}.at n=26A064842
- Centered 15-gonal numbers: a(n) = (15*n^2 - 15*n + 2)/2.at n=29A069128
- Group successively larger composite numbers so that the sum of the n-th group is a multiple of n. Sequence gives the sum of the terms in the n-th group.at n=25A074120
- Numbers k for which phi(k) = phi(k+1) - phi(k-1).at n=20A076529
- a(n) = n*(n^2+3*n-1)/3.at n=26A084990