15793
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 16740
- Proper Divisor Sum (Aliquot Sum)
- 947
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14848
- Möbius Function
- 1
- Radical
- 15793
- 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
- 40
- 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 parallelogram polyominoes with n cells (also called staircase polyominoes, although that term is overused).at n=12A006958
- Coordination sequence for MgNi2, Position Mg2.at n=31A009935
- Strong pseudoprimes to base 40.at n=19A020266
- Strong pseudoprimes to base 46.at n=22A020272
- Numbers k such that the continued fraction for sqrt(k) has period 73.at n=11A020412
- Expansion of Product_{m>=1} (1-m*q^m)^-4.at n=8A022728
- Sizes of successive balls in D_4 lattice.at n=39A046949
- Number of 1324-avoiding permutations of length n.at n=8A061552
- a(n) = sum(sum(binomial(j-n-1,m),m=0..n),j=0..n).at n=8A092785
- a(1)=1, a(2)=2; for n >= 2, a(n+1) = a(n) + sum of prime factors of a(n).at n=32A096461
- Records in A117677.at n=45A117679
- Numbers n such that 10^n - 81 is prime.at n=15A178437
- a(n) = n^2 + 731*n + 1.at n=21A180919
- Numbers k such that 3*R_(k+2) + 2*10^k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=22A256788
- The total number of different isosceles trapezoids, excluding squares, that can be drawn on an n X n square grid where the corners of each individual trapezoid lie on a lattice point.at n=33A272459
- Expansion of 1/(1 - Sum_{k>=0} x^((2*k+1)^2)).at n=54A280863
- Numbers k such that (265*10^k + 11)/3 is prime.at n=20A283448
- Triangle read by rows: T(n,k) = T(n-k,k-1) + 2*T(n-k,k) + T(n-k,k+1) with T(0,0) = 1 for 0 <= k <= A003056(n).at n=46A291929
- a(n) = n*Fibonacci(n) + ((-1)^n + 1)/2.at n=16A324129
- Irregular table read by rows: T(n,k) is the number of permutations in S_n that have exactly k occurrences of the pattern 1324. 0 <= k <= A342853(n).at n=31A342861