8507
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 8736
- Proper Divisor Sum (Aliquot Sum)
- 229
- 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
- 8280
- Möbius Function
- 1
- Radical
- 8507
- 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
- 78
- 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 subsets of { 1, ..., n } containing an A.P. of length 7.at n=17A018792
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly seven 1's.at n=40A020443
- Smallest value of x such that M(x) = n, where M() is Mertens's function A002321.at n=31A051400
- Inverse Mertens function: smallest k such that |M(k)| = n, where M(x) is Mertens's function A002321.at n=31A051402
- T(n,n-3), array T as in A054106.at n=36A054107
- Binomial transform of A001037.at n=10A054190
- An inverse to Mertens's function: smallest k >= 2 such that Mertens's function |M(k)| (see A002321) is equal to n.at n=32A060434
- Smallest k such that |M(k)| = 2^n, where M(x) is Mertens's function A002321.at n=5A084235
- Expansion of x*(-1+2*x-3*x^3+x^4)/((x^3+x^2+x-1) * (x-1)^2).at n=15A121986
- Least semiprime s for which the Mertens function M(s) = n.at n=35A123173
- A144325(n) + A144313(n) + A144315(n).at n=18A144715
- Number of n X n binary arrays symmetric about both diagonal and antidiagonal with all ones connected only in a 11000-01110-00011 pattern in any orientation.at n=17A147189
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, 1), (0, 0, 1), (0, 1, 0), (1, 0, -1)}.at n=8A149896
- Minimal exponents m such that the fractional part of (Pi-2)^m obtains a minimum (when starting with m=1).at n=10A153717
- a(n) = round((5^n)*4 / 3^n).at n=15A228079
- Sum of all aliquot divisors of all positive integers <= prime(n).at n=37A244578
- Terms in A247665 which are neither primes nor prime powers, in order of appearance.at n=48A248391
- Numbers k such that (107*10^k + 13)/3 is prime.at n=20A291659
- MM-numbers of labeled simple hypergraphs with no singletons spanning an initial interval of positive integers.at n=18A320463
- MM-numbers of labeled multi-hypergraphs with no singletons spanning an initial interval of positive integers.at n=22A320464