5187
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 8960
- Proper Divisor Sum (Aliquot Sum)
- 3773
- 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
- 2592
- Möbius Function
- 1
- Radical
- 5187
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 41
- 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
- no
- Odd
- yes
Appears in sequences
- Number of sublattices of index n in generic 3-dimensional lattice.at n=41A001001
- Numbers k such that phi(k) = phi(k+1).at n=16A001274
- a(n) = floor(n*(n+2)*(2*n-1)/8).at n=26A007518
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 4.at n=40A013592
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 5.at n=16A013593
- Expansion of g.f. 1/((1-2*x)*(1-5*x)).at n=5A016127
- a(n) = [ a(n-1)/a(1) ] + [ a(n-3)/a(3) ] + [ a(n-5)/a(5) ] + ..., for n >= 3.at n=32A022878
- Number of partitions of n into 6 unordered relatively prime parts.at n=44A023026
- Expansion of Molien series for 8-dimensional real Clifford group 2^{1+6}.Alt_8.2 of genus 3 and order 5160960.at n=42A024186
- 7 times triangular numbers: 7*n*(n+1)/2.at n=38A024966
- Number of distinct products ijk with 0 <= i < j < k <= n.at n=46A027429
- 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 48.at n=15A031546
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 48.at n=2A031726
- Divisors = 3 (mod 4) of Descartes's 198585576189.at n=41A033871
- a(n) = n*(n+1)*(5*n+1)/6.at n=17A033994
- a(1)=10; if n = Product p_i^e_i, n > 1, then a(n) = Product p_{i+1}^e_i * Product p_{i+3}^e_i.at n=21A045973
- Squarefree odd numbers with exactly 4 distinct prime factors.at n=26A046390
- a(n+1) = 1 + Sum_{k=0..n} binomial(n,k)*a(k)*a(n-k) for n >= 0 with a(0) = 1.at n=6A054687
- Number of primitive sublattices of index n in generic 3-dimensional lattice.at n=41A060983
- Squarefree numbers k such that phi(k) = phi(k+1).at n=9A063739