8751
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
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 11672
- Proper Divisor Sum (Aliquot Sum)
- 2921
- 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
- 5832
- Möbius Function
- 1
- Radical
- 8751
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 52
- 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
- Total height of trees with n nodes.at n=10A001853
- Numbers that are the sum of 7 positive 7th powers.at n=26A003374
- Harmonic Molien series for Conway group Con.0.at n=40A008924
- Sum of digits in n-th term of A022470.at n=29A022475
- Numbers k such that k^2 and k^3 have the same set of digits.at n=10A029797
- 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=26A031560
- Trimorphic numbers: n^3 ends with n. Also m-morphic numbers for all m > 5 such that m-1 is not divisible by 10 and m == 3 (mod 4).at n=33A033819
- Decimal part of a(n)^(1/4) starts with a 'nine digits' anagram.at n=1A034279
- Trimorphic but not bimorphic nor automorphic.at n=25A056032
- Perfect totient numbers.at n=21A082897
- Perfect totient numbers, omitting powers of 3.at n=13A091847
- Number of positive integers <= 10^n that are divisible by no prime exceeding 19.at n=6A108276
- Numbers k such that the k-th and (k+1)-th primes have the same sum of squares of digits.at n=35A109182
- Positive integers n such that S(n) divides n, where S(n) is the sum of the iterates of the Euler phi-function of n, that is, S(n) = phi(n)+phi(phi(n))+....+ 1.at n=42A113808
- Descending dungeons: see Comments lines for definition.at n=18A121263
- a(n) = 625*n + 1.at n=13A158383
- a(n) = 14*n^2 + 1.at n=24A158482
- 1+5*n+7*n^2.at n=34A168235
- A175366(n^2).at n=39A175367
- Numbers n with k digits such that n^2 == 1 (mod 10^k).at n=17A181607