4640
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 11340
- Proper Divisor Sum (Aliquot Sum)
- 6700
- 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
- 1792
- Möbius Function
- 0
- Radical
- 290
- Omega Function (Ω)
- 7
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 121
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 Product_{k>=1} (1 - x^k)^16.at n=13A000739
- A B_2 sequence: a(n) = least value such that sequence increases and pairwise sums of distinct elements are all distinct.at n=50A011185
- a(n) = n*(11*n+1)/2.at n=29A022269
- a(n) = (d(n)-r(n))/2, where d = A026046 and r is the periodic sequence with fundamental period (0,1,0,1).at n=26A026047
- Duplicate of A022269.at n=28A026817
- Numbers n such that n divides the (left) concatenation of all numbers <= n written in base 21 (most significant digit on right and removing all least significant zeros before concatenation).at n=8A029538
- 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 33.at n=22A031531
- Numbers k such that 255*2^k+1 is prime.at n=28A032504
- Expansion of (1 + x)/(1 - 2*x - x^2 + x^3).at n=10A033303
- Numbers whose base-4 representation contains exactly four 0's and two 2's.at n=13A045059
- Triangular array generated by its row sums: T(n,0)=1 for n >= 0, T(1,1)=2, T(n,k)=T(n,k-1)+d*r(n-k) for k=2,3,...,n, d=(-1)^(k+1), n >= 2, r(h)=sum of the numbers in row h of T.at n=39A054098
- T(n,3), array T as in A054098.at n=5A054105
- a(n) = n^3 - n^2 + n - 1 = (n-1) * (n^2 + 1).at n=17A062158
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 67 ).at n=25A063340
- Consider the sequence b(k) such that b(k) and sigma(b(k)) end with the same digit in base 10. Sequence gives values of b(k) such that b(k)/k = 10.at n=8A065255
- Number of partitions of n into squarefree parts.at n=36A073576
- Expansion of (1-x)/(1+2*x-x^2-x^3).at n=10A078056
- Indices k where A057176(k) = 2.at n=12A086809
- Triangle read by rows: fraction of integers having k of the first n positive integers as divisors is T(n,k)/A003418(n).at n=57A096180
- Numerators of e.g.f.: -cot(arctanh(x)), odd powers only.at n=3A102064