15593
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 16128
- Proper Divisor Sum (Aliquot Sum)
- 535
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15060
- Möbius Function
- 1
- Radical
- 15593
- 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
- 84
- 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
- Numbers whose base-5 representation contains exactly three 3's and three 4's.at n=19A045307
- Least number k such that k has n anti-divisors.at n=43A066464
- Number of anti-divisors of n (A066272) sets a record.at n=24A073638
- Number of nonisomorphic partitions of n on the Ferrers diagram.at n=39A095814
- Let pi be an unrestricted partition of n with the summands written as binary numbers; a(n) is the number of such partitions with an even number of binary ones.at n=39A102425
- a(n) = reverse(2^n) mod 2^n.at n=13A103166
- Partial sums of A102540 (primes that are not Chen primes).at n=41A115606
- a(n) = 5^n - 2^(n - 1) for n > 0; a(0) = 1.at n=6A144465
- Conjectured positive numbers which have more than one representation (m,s) as a difference s^2 - m^5, m >= 1, s > 0.at n=34A177770
- Monotonic ordering of nonnegative differences 5^i-2^j, for 40>=i>=0, j>=0.at n=47A192115
- Numbers n such that Sum(1/d*_n)>Sum(1/d*_m) for all m<n, where d*_n and d*_m are the anti-divisors of n and m.at n=15A192294
- Fibonacci sequence beginning 11, 9.at n=16A206422
- Number of 2 X 2 matrices having all terms in {1,...,n} and determinant in [-n,n].at n=16A211069
- The number of n X n upper triangular (0,1)-matrices M with all diagonal entries 1 such that M = f(M^2) and sum(row 1) >= sum(row 2) >= ... >= sum(row n-1) >= sum(row n) = 1 and f maps any nonzero entry to 1.at n=6A213430
- A213784/12.at n=26A213789
- Number of (n+2)X(2+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4.at n=5A252059
- Number of (n+2)X(6+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4.at n=1A252063
- T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4.at n=22A252065
- T(n,k)=Number of (n+2)X(k+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4.at n=26A252065
- a(n) is the smallest nonnegative k such that there is no 3 X 3 matrix with entries in {1,...,n} whose determinant is k.at n=21A262719