8541
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 13468
- Proper Divisor Sum (Aliquot Sum)
- 4927
- 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
- 5184
- Möbius Function
- 0
- Radical
- 2847
- Omega Function (Ω)
- 4
- 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
- 65
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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 k*(k+6) is a palindrome.at n=9A028561
- Numerators of continued fraction convergents to sqrt(774).at n=8A042492
- 2-ranks of difference sets constructed from Glynn type I hyperovals.at n=14A049112
- Local ranks of terms of A057122.at n=44A057124
- Maximum value taken on by f(P) = Sum_{i=1..n} p(i)*p(n+1-i) as {p(1),p(2),...,p(n)} ranges over all permutations P of {1,2,3,...,n}.at n=29A087035
- a(n) is the least positive integer such that nextprime(a(n)^n) - prevprime(a(n)^n) = 4.at n=20A090125
- Iccanobirt numbers (9 of 15): a(n) = R(a(n-1) + a(n-2) + R(a(n-3))), where R is the digit reversal function A004086.at n=13A102119
- Numbers k such that the decimal digits of phi(k) are a permutation of those of k.at n=19A115921
- a(n) = number of solutions to the Diophantine equation x+y^2+z^3=n^4 with positive x,y,z.at n=15A121876
- Odd interprimes divisible by 13.at n=36A124619
- Number of magic labelings of the Petersen graph with magic sum n.at n=10A125196
- Catalan transform of the 3-Fibonacci sequence A006190.at n=7A143646
- a(n) = 12*n^2 - 8*n + 9.at n=26A167585
- A121153 \ A005836.at n=8A170830
- Records in A031883 (positions).at n=11A171924
- Index of first occurrence of 2n in A031883, or 0 if 2n never occurs in A031883 = first differences of lucky numbers A000959.at n=49A181558
- Number of lattice paths from (0,0) to (n,n) using steps (1,0), (2,0), (0,2), (1,1).at n=7A192368
- Second 13-gonal numbers: a(n) = n*(11*n+9)/2.at n=39A211013
- Numbers k such that k^2 +- k +- 1 is prime for all four possibilities.at n=8A236056
- Solutions to phi(n) = phi(sigma(n)) that are not given by Theorem 3 of Golomb's manuscript.at n=50A260021