8345
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10020
- Proper Divisor Sum (Aliquot Sum)
- 1675
- 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
- 6672
- Möbius Function
- 1
- Radical
- 8345
- 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
- 114
- 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
- Numbers k such that the continued fraction for sqrt(k) has period 25.at n=26A020364
- Numbers in which 0,1,2,3,4,5 all occur in base 6.at n=0A031947
- Digitally balanced numbers in base 6: equal numbers of 0's, 1's, ..., 5's.at n=0A049357
- a(1) = 1; for n > 1, smallest digitally balanced number in base n.at n=5A049363
- Numbers n such that the partition function A000041(k) is even and odd the same number of times for 0 <= k <= n.at n=37A098936
- Prime numbers concatenated with 45.at n=22A137521
- Numbers k such that the continued fraction of (1 + sqrt(k))/2 has period 15.at n=35A146338
- Let f(m) = number of steps needed to reach a Harshad number when the map k->A062028(l) is iterated starting at m; a(n) = smallest m such that f(m) = n.at n=86A181664
- Number of strings of numbers x(i=1..7) in 0..n with sum i^3*x(i) equal to 343*n.at n=10A184262
- Numbers k such that tau(k-1) = (tau(k))^2 = tau(k+1), where tau(k) = A000005(k) (number of divisors of k).at n=31A190266
- Number of subsets of {1..n} (including empty set) such that the pairwise GCDs of elements are not distinct.at n=24A196720
- Number of representations of n as a sum of products of pairs of positive integers, n = Sum_{k=1..m} i_k*j_k with i_k<=j_k, i_k<=i_{k+1}, j_k<=j_{k+1}, i_k*j_k<=i_{k+1}*j_{k+1}.at n=30A212214
- Number of (n+1)X(2+1) 0..2 arrays with the difference of the upper and lower median value of each 2X2 subblock in lexicographically nondecreasing order rowwise and columnwise.at n=1A235561
- T(n,k) = Number of (n+1) X (k+1) 0..2 arrays with the difference of the upper and lower median value of each 2 X 2 subblock in lexicographically nondecreasing order rowwise and columnwise.at n=4A235565
- Sum of all proper divisors of all positive integers <= prime(n).at n=37A244576
- Number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 291", based on the 5-celled von Neumann neighborhood.at n=49A271129
- Irregular array by rows: A(n,m) is the least number which gives a pandigital product when multiplied by the m-th repunit in base n; each row is truncated when it reaches its stationary point.at n=10A277055
- Square array A(n, k) read by descending antidiagonals, where column k is the expansion of the e.g.f. exp(k*x)/(2 - exp(x)).at n=50A292915
- Solution of the complementary equation a(n) = a(n-1) + a(n-2) + b(n-1) + b(n-2) - n, where a(0) = 1, a(1) = 2, b(0) = 3, and (a(n)) and (b(n)) are increasing complementary sequences.at n=15A294553
- Expansion of e.g.f. tanh(x*tan(x/2)) (even powers only).at n=5A296853