17850
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 48
- Divisor Sum
- 53568
- Proper Divisor Sum (Aliquot Sum)
- 35718
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3840
- Möbius Function
- 0
- Radical
- 3570
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 5
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
- 97
- 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
- a(n) = floor(n*(n+2)*(2*n-1)/8).at n=40A007518
- Expansion of Sum_{n>=0} (q^n / Product_{k=1..n+4} (1 - q^k)).at n=32A035300
- Numbers k such that 53*2^k-1 is prime.at n=15A050552
- (Terms in A029661)/2.at n=49A051430
- (Terms in A029647)/2.at n=50A051471
- a(n) = n*(n+1)*(n^2+5*n+18)/24.at n=23A051744
- Successive maxima in sequence A007365.at n=11A065933
- Composite numbers k such that the difference between the odd and even aliquot parts of k divides k.at n=20A066193
- Numbers k such that k+1, k^2+1 and k^4+1 are primes.at n=37A070325
- Trisection of A007294.at n=38A073471
- Sigma unitary-sigma perfect numbers: numbers m which satisfy the following equation for some integer k: sigma(usigma(m)) = k*m where usigma(m) is sum of unitary divisors of m.at n=23A083288
- Least common multiple of numbers obtained by adding one to the odd divisors of n and subtracting 1 from the even divisors of n.at n=51A086536
- Row sums of A059450.at n=6A086871
- a(n) = n*(n+1)*(n^2-2*n+2)/2.at n=14A101375
- Numbers k such that 4*k-1, 8*k-1, 16*k-1 and 32*k-1 are all primes.at n=10A101794
- a(n) = n^5 + 3*n^3 + 2*n = n*(n^2 + 1)*(n^2 + 2).at n=6A120573
- Expansion of 1/(1-x^2-x^3-x^6).at n=32A121833
- Triangle of coefficients of q in e.g.f. that satisfies: A(x,q) = exp( q*x*A(q*x,q) ), read by rows of [n*(n-1)/2 + 1] terms in row n for n>=0.at n=57A126265
- Triangle read by rows: T(n,k) is the number of paths in the right half-plane, from (0,0) to (n,0), consisting of steps U=(1,1), D=(1,-1), h=(1,0) and H=(2,0), having k U steps (0 <= k <= floor(n/2)).at n=40A132886
- Number of 1-sided strip polyrhombs with n cells.at n=12A151523