8913
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 11888
- Proper Divisor Sum (Aliquot Sum)
- 2975
- 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
- 5940
- Möbius Function
- 1
- Radical
- 8913
- 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
- 47
- 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
- Number of nonnegative solutions to x^2 + y^2 + z^2 <= n^2.at n=25A000604
- a(n) is the solution to the postage stamp problem with 4 denominations and n stamps.at n=26A001209
- Numbers k such that the continued fraction for sqrt(k) has period 78.at n=22A020417
- 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 62.at n=35A031560
- Base 8 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,3.at n=4A037636
- Least number beginning with prime(n) such that every concatenation is a prime.at n=23A090508
- Expansion of (1-x)^2/((1-x)^3-4x^4).at n=13A097121
- Number of partitions of n into deficient numbers.at n=34A097797
- Number of partitions of the n-th deficient number into deficient numbers.at n=27A097799
- a(1)=1. a(n) = Sum_{1<=k<n, gcd(k,n(n+1))=1} a(k).at n=37A125596
- Number of n X n binary arrays with all ones connected only in a 1100-0111-1100 pattern in any orientation.at n=7A146674
- Number of n X n binary arrays symmetric under horizontal and vertical reflection with all ones connected only in a 1100-0111-1100 pattern in any orientation.at n=17A146676
- Partial sums of A138202.at n=17A164940
- Position of 5^n in A051037 (5-smooth numbers).at n=24A188427
- Number of (n+1) X 3 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero.at n=7A204707
- T(n,k) is the number of (n+1) X (k+1) 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero.at n=37A204713
- T(n,k) is the number of (n+1) X (k+1) 0..1 arrays with the permanents of all 2 X 2 subblocks equal and nonzero.at n=43A204713
- Numbers that match polynomials over {0,1} that have a factor containing 3 as a coefficient; see Comments.at n=13A208181
- a(1)=9; thereafter a(n) = 8*10^(n-1) + 8 + a(n-1).at n=3A232229
- Number of partitions p of n such that (sum of parts with multiplicity 1) < (sum of all other parts).at n=36A240448