8003
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8208
- Proper Divisor Sum (Aliquot Sum)
- 205
- 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
- 7800
- Möbius Function
- 1
- Radical
- 8003
- 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
- 44
- 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
- Row sums of Fibonacci-Pascal triangle in A045995.at n=6A006449
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly nine 1's.at n=27A020445
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = A001950 (upper Wythoff sequence).at n=22A024689
- Maximal base 7 run length is 4.at n=32A037991
- Numbers whose base-7 representation contains exactly four 2's.at n=26A043404
- Numbers whose base-6 representation has exactly 6 runs.at n=4A043614
- Nonnegative numbers of the form n^3 (+/-) 3, n >= 0.at n=39A052276
- Sum of a(n) terms of 1/k^(8/9) first exceeds n.at n=16A056185
- a(n) = Sum_{k=1..n} antisigma(k), where antisigma(i) = sum of the nondivisors of i that are between 1 and i.at n=36A076664
- Least nontrivial multiple of the n-th prime beginning with 8.at n=35A078292
- Composite numbers k such that the continued fraction for k/m contains no 2 for any 1 <= m <= k.at n=29A082409
- a(n) = n^3 + 3.at n=20A084378
- A096780(A096780(n)).at n=22A096782
- a(n) = a(n-1) - 2*a(n-2) - 3*a(n-3) - ... - (n-1)*a(1), with a(1) = a(2) = 1, a(3) = -1.at n=14A106540
- Start with 1 and repeatedly reverse the digits and add 62 to get the next term.at n=35A118157
- Number of binary strings of length n such that there exist three consecutive digits where at least two of them are 1's.at n=13A118645
- a(n) = 20*n^2 + 3.at n=19A167573
- A symmetrical triangle sequence:q=2;c(n,q)=Product[1 - q^i, {i, 1, n}];t(n,m,q)=-Eulerian[n + 1, m] + 2*c(n, q)/(c(m, q)*c(n - m, q)).at n=31A176427
- A symmetrical triangle sequence:q=2;c(n,q)=Product[1 - q^i, {i, 1, n}];t(n,m,q)=-Eulerian[n + 1, m] + 2*c(n, q)/(c(m, q)*c(n - m, q)).at n=32A176427
- Numbers m having the same sum of divisors as m+20 has.at n=22A181647