8742
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
- 4
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 18432
- Proper Divisor Sum (Aliquot Sum)
- 9690
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2760
- Möbius Function
- 1
- Radical
- 8742
- 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
- yes
Recreational
- Happy Number
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 109
- 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
- Expansion of e.g.f. 6*exp(x)/(1-x)^4.at n=4A001341
- a(n) = Sum_{k = 0..4} (n+k)! C(4,k).at n=4A001346
- Expansion of 1/(1-x^10-x^11-x^12-x^13-x^14-x^15-x^16-x^17-x^18-x^19-x^20).at n=69A017896
- a(n) = dot_product(1,2,...,n)*(5,6,...,n,1,2,3,4).at n=26A026043
- Decimal part of cube root of a(n) starts with 6: first term of runs.at n=18A034132
- Multiplicity of highest weight (or singular) vectors associated with character chi_58 of Monster module.at n=36A034446
- Number of partitions of n into parts not of forms 4*k+2, 20*k, 10*k+5.at n=50A036026
- Hexagonal matchstick numbers: a(n) = 3*n*(3*n+1).at n=31A045945
- Lengths of successive generations of the Kolakoski sequence A000002.at n=20A054352
- Binomial triangle based on factorials.at n=32A076571
- 4-almost primes equal to the product of two successive semiprimes.at n=31A108215
- Expansion of psi(q^5)/psi(q) in powers of q where psi() is a Ramanujan theta function.at n=50A116494
- Numbers k for which 14*k+1, 14*k+5, 14*k+11 and 14*k+13 are primes.at n=28A123987
- Odious oblong (promic) numbers.at n=36A130201
- Expansion of f(q) * f(q^5) / phi(-q^2)^2 in powers of q where f(), phi() are Ramanujan theta functions.at n=25A145722
- a(n) = (4*n+1)*(4*n+2) = (4*n+2)!/(4*n)!.at n=23A157870
- Number of reduced words of length n in Coxeter group on 4 generators S_i with relations (S_i)^2 = (S_i S_j)^8 = I.at n=8A164697
- Principal diagonal of the convolution array A213783.at n=35A213759
- a(n) is the conjectured highest power of n which has no four identical digits in succession.at n=11A216065
- Squarefree oblong numbers.at n=31A229882