10421
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 11052
- Proper Divisor Sum (Aliquot Sum)
- 631
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9792
- Möbius Function
- 1
- Radical
- 10421
- 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
- 104
- 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
- G.f.: -1 + Product_{k>=1} (1 + prime(k)*x^prime(k)).at n=35A002099
- a(n) = ceiling(n*phi^13), where phi is the golden ratio, A001622.at n=20A004968
- Pseudoprimes to base 35.at n=26A020163
- Conjectured number of irreducible multiple zeta values of depth 9 and weight 2n+25.at n=12A022497
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 12.at n=17A031690
- Numbers k such that 65*2^k+1 is prime.at n=34A032382
- Multiplicity of highest weight (or singular) vectors associated with character chi_10 of Monster module.at n=40A034398
- Sum of consecutive nonsquares.at n=17A048395
- a(n) = sum of modular offsets: mod[n+c,b]-(mod[n,b]+c) for c<=b<=n.at n=45A066809
- Numbers m such that [A070080(m), A070081(m), A070082(m)] is an acute scalene integer triangle with prime side lengths.at n=29A070123
- a(n) = 36*n^2 + n.at n=16A157324
- a(n) = 289*n^2 + 17.at n=6A158585
- A triangular sequence:t(n,m)=A033306(n,m)-A033306(n,0)+1.at n=39A174640
- A triangular sequence:t(n,m)=A033306(n,m)-A033306(n,0)+1.at n=41A174640
- Number of subwords of type dh^ju (j>=1), where u=(1,1), h=(1,0), and d=(1,-1), in all peakless Motzkin paths of length n (can be easily expressed using RNA secondary structure terminology).at n=15A190163
- Row sums of the triangle in A199332.at n=33A199771
- Number of 0..n arrays x(0..2) of 3 elements with each no smaller than the sum of its previous elements modulo (n+1).at n=32A200252
- Number of (w,x,y,z) with all terms in {1,...,n} and w + x = 2y + 2z.at n=35A212561
- Unchanging value maps: number of nX4 binary arrays indicating the locations of corresponding elements unequal to no king-move neighbor in a random 0..2 nX4 array.at n=6A219447
- Unchanging value maps: number of n X 7 binary arrays indicating the locations of corresponding elements unequal to no king-move neighbor in a random 0..2 n X 7 array.at n=3A219450