9877
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 31
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12096
- Proper Divisor Sum (Aliquot Sum)
- 2219
- 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
- 7872
- Möbius Function
- -1
- Radical
- 9877
- Omega Function (Ω)
- 3
- Little Omega Function (ω)
- 3
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
- 135
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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) = [ a(n-1)/a(1) ] + [ a(n-3)/a(3) ] + [ a(n-5)/a(5) ] + ..., for n >= 3.at n=24A022860
- n written in fractional base 10/9.at n=37A024664
- Numbers k such that k^4 can be written as a sum of four positive 4th powers with no common factor.at n=35A039664
- Numerators of continued fraction convergents to sqrt(291).at n=2A041546
- Numbers whose base-4 representation contains exactly four 1's and three 2's.at n=29A045108
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-1)/3.at n=23A048007
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-2)/3.at n=23A048018
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-3)/3.at n=23A048029
- a(n) is the first of a triple of consecutive integers, each of which is the product of three distinct primes.at n=20A066509
- Numbers k such that 10^k+9^(k-1) is prime.at n=19A096186
- Odd interprimes divisible by 17.at n=32A124620
- Partial sums of A151779.at n=38A151781
- a(n) = 343*n - 70.at n=28A157374
- Composite numbers n such that 8*n^2-2*n-1 divides the primitive part U(n) of Fibonacci(n).at n=21A159234
- Antonym of A014824: each term is 10 times the previous term minus n.at n=3A179477
- Number of (w,x,y,z) with all terms in {0,...,n} and w=2*floor((x+y+z)/2).at n=36A212748
- The decimal digits of n appear n times in the decimal representation of n!.at n=4A264688
- a(n) is the number of domino towers with n bricks up to horizontal flipping.at n=9A264746
- Halogen sequence: a(n) = A018227(n)-1.at n=36A271999
- a(n) = n*(2*n^2 + 3), n >= 1; a(0)=1.at n=17A288534