8857
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9396
- Proper Divisor Sum (Aliquot Sum)
- 539
- 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
- 8320
- Möbius Function
- 1
- Radical
- 8857
- 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
- 109
- 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
- a(n) = floor(n*phi^13), where phi is the golden ratio, A001622.at n=17A004928
- a(n) = round(n*phi^13), where phi is the golden ratio, A001622.at n=17A004948
- Strong pseudoprimes to base 43.at n=11A020269
- Numbers k such that the continued fraction for sqrt(k) has period 53.at n=15A020392
- Numbers whose set of base-9 digits is {1,3}.at n=40A032916
- Every run of digits of n in base 16 has length 2.at n=38A033014
- a(n) = a(n-1) + a(round(2*(n-1)/3)) + a(round((n-1)/3)) with a(1)=1, a(2)=2.at n=31A033500
- Base 9 digits are, in order, the first n terms of the periodic sequence with initial period 1,3.at n=4A037581
- Composite numbers not divisible by 5 which in base 5 contain their largest proper factor as a substring.at n=3A063889
- Semiprimes p1*p2 such that p2 > p1 and p2 mod p1 = 11.at n=30A064909
- Numbers k such that there are exactly 8 numbers j for which binomial(k, floor(k/2)) / binomial(k,j) is an integer, i.e., A080383(k) = 8.at n=46A080386
- Structured truncated tetrahedral numbers.at n=16A100156
- Numbers n such that 8*10^n + 9 is prime.at n=22A103070
- 4th diagonal of triangle in A059317.at n=36A106058
- Semiprimes n such that 3*n - 2 is a square.at n=46A112393
- Semiprimes in A056109.at n=24A113528
- a(n) = 15*n^2 + 9*n + 1.at n=24A134153
- Triangle T(n, k, q) = e(n, k, q), where e(n, k, q) = ((1 - (-q)^(n+k-1))/(1 + q))*e(n-1, k, q) + (-q)^(n+k-2)*e(n-1, k-1, q), e(n, 0, q) = e(n, n, q) = 1, and q = 2, read by rows.at n=12A156539
- a(n) = 5*n^2 + 11*n + 1.at n=41A172044
- Partial sums of round(3^n/10).at n=10A177881