8126
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
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12960
- Proper Divisor Sum (Aliquot Sum)
- 4834
- 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
- 3808
- Möbius Function
- -1
- Radical
- 8126
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 65
- 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
- Smallest nonnegative number that is the sum of 3 squares in exactly n ways.at n=39A000437
- Smallest number that is the sum of 3 squares in at least n ways.at n=39A000451
- Values of m in the discriminant D = -4*m leading to a new maximum of the L-function of the Dirichlet series L(1) = Sum_{k=1..oo} Kronecker(D,k)/k.at n=21A003420
- a(n) is the smallest number that is the sum of 3 nonzero squares in exactly n ways.at n=39A025414
- Least sum of 3 distinct nonzero squares in exactly n ways.at n=39A025415
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 90.at n=2A031588
- Numbers whose base-4 representation contains exactly two 2's and four 3's.at n=26A045147
- Smallest Maris-McGwire k-tuple (k>1) for each k: f(n) = f(n+1) = ... = f(n+k-1), where f is defined in comments.at n=2A045760
- Numbers k such that k^14 == 1 (mod 15^3).at n=9A056087
- Numbers k such that prime(k) + prime(k+1) is a square.at n=25A064397
- Squared radii of the spheres around (0,0,0) that contain record numbers of lattice points.at n=46A071609
- a(n) = 7*n^2 + n.at n=34A092277
- Least positive number having exactly n partitions into three squares.at n=39A095809
- a(n) = n-th centered n-gonal number.at n=25A100119
- Least integer that can be written as a sum of 3 squares in n nontrivial ways (ignoring order and signs).at n=40A122699
- Smallest positive integer which can be expressed as the ordered sum of 3 squares in exactly n different ways.at n=40A124970
- a(0)=1; for n > 0, a(n) = a(n-1) + a(prime(n)(mod n)), where prime(n) is the n-th prime.at n=44A127066
- Numbers k such that prime(k) + prime(k+1) is a perfect power.at n=31A132746
- a(n) = 625*n + 1.at n=12A158383
- Numbers of espalier polycubes of a given volume in dimension 5.at n=19A229925