5561
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5712
- Proper Divisor Sum (Aliquot Sum)
- 151
- 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
- 5412
- Möbius Function
- 1
- Radical
- 5561
- 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
- 129
- 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
- Smallest nonnegative number that is the sum of 3 squares in exactly n ways.at n=33A000437
- Smallest number that is the sum of 3 squares in at least n ways.at n=33A000451
- Smallest number that is the sum of 3 squares in at least n ways.at n=32A000451
- 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=19A003420
- Coordination sequence T1 for Zeolite Code EUO.at n=46A008095
- Numbers k giving rise to prime quadruples (30k+11, 30k+13, 30k+17, 30k+19).at n=46A014561
- Numbers k such that the continued fraction for sqrt(k) has period 54.at n=29A020393
- a(n) is the smallest number that is the sum of 3 nonzero squares in exactly n ways.at n=33A025414
- Least sum of 3 distinct nonzero squares in exactly n ways.at n=31A025415
- Numbers k such that k-th and (k+1)-st term of A038593 differ by 6.at n=30A038637
- To get next term, multiply by 17, add 1 and discard any prime factors < 17.at n=15A057216
- To get next term, multiply by 17, add 1 and discard any prime factors < 17.at n=37A057216
- a(n) = Sum_{i=1..n} i^(n - i) + (n - i)^i.at n=8A062810
- Numbers k such that the product of the digits of k is equal to the sum of the prime factors of k, counted with multiplicity.at n=21A065774
- Numbers n such that the sum of the prime factors of n equals the product of the digits of n.at n=17A067173
- Squared radii of the spheres around (0,0,0) that contain record numbers of lattice points.at n=41A071609
- a(n) = A077710(n+1)/A077710(n).at n=9A077711
- a(n) = Sum_{d divides n} d^(n/d + 1).at n=17A078308
- First row of array in A081998.at n=43A081999
- Numbers containing no zero digits in bases 3 to 10.at n=14A085509