10826
domain: N
Properties
Digital Properties
- Digit Count
- 5
- 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
- 16242
- Proper Divisor Sum (Aliquot Sum)
- 5416
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5412
- Möbius Function
- 1
- Radical
- 10826
- 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
- 42
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 8.at n=19A031421
- a(n) = Sum_{i=0..n} T(i,n-i), array T as in A049723.at n=21A049724
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 4.at n=37A050036
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2, and a(3) = 4.at n=37A050052
- a(n) = a(n-1) + a(m) for n >= 3, where m = 2*n - 3 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1 and a(2) = 3.at n=37A050068
- Matrix square of triangle A063967.at n=40A091700
- Bisection of A096441.at n=28A096967
- a(n) is the smallest integer k such that the n-th (backward) difference of the partition sequence A000041 is positive from k onwards.at n=26A155861
- Number of nondecreasing arrangements of n numbers in -3..3 with sum zero and sum of squares less than n*12/3.at n=25A183929
- Array read by antidiagonals, m>=0, n>=0, A(m,n) = sum{k=0..n} sum{j=0..m} sum{i=0..m} (-1)^(j+i)*C(i,j)*n^j*k^(m-j).at n=59A198061
- a(n) = binary code (shown here in decimal) of the position of natural number n in the beanstalk-tree A218776.at n=34A218615
- a(n) = binary code (shown here in decimal) of the position of the predecessor of the natural number pair (2n,2n+1) in the compact beanstalk-tree A218780.at n=18A218791
- Number of partitions of n such that 2*(greatest part) <= (number of parts).at n=42A237752
- Dimensions of algebraic generators of combinatorial Hopf algebra H(Heap_2).at n=5A247639
- G.f. satisfies: A(x) = A(x^2 + 2*x^3)/(1-x).at n=15A251581
- Composite numbers n such that Sum_{k = 0..n} (-1)^k * C(n,k) * C(2*n,k) == -1 (mod n^3) (see A234839).at n=22A268303
- T(i, j) = k is the least squarefree number with a run of exactly i>=0 nonsquarefree numbers immediately preceding k and a run of exactly j>=0 nonsquarefree numbers immediately succeeding k.at n=25A270996
- Numbers missing from A001032 despite satisfying the necessary congruence conditions (see comments).at n=23A274469
- Numbers missing from A134419 despite satisfying the necessary congruence conditions (see comments).at n=27A274471
- Numbers k such that 10^k - 800001 is prime.at n=17A288822