16562
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 31293
- Proper Divisor Sum (Aliquot Sum)
- 14731
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6552
- Möbius Function
- 0
- Radical
- 182
- Omega Function (Ω)
- 5
- 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
- 159
- 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
- yes
- Odd
- no
Appears in sequences
- [ 4th elementary symmetric function of {sqrt(k)} ], k = 1,2,...,n.at n=8A025195
- Numbers n such that n | 10^n + 9^n + 1.at n=33A057295
- Sum of terms in n-th row of A077164.at n=25A077167
- Spt function: total number of smallest parts (counted with multiplicity) in all partitions of n.at n=27A092269
- Half the number of n X n binary matrices differing in at most one position between adjacent rows and at most one position between adjacent columns.at n=8A140336
- Records in A071786.at n=41A151766
- a(n) = A066186(n) - A004125(n).at n=20A162362
- a(n) = n^2*(n+1)^2/2.at n=13A163102
- Expansion of 2*(1 -4*x +14*x^2 +4*x^3 +9*x^4)/(1-x)^5.at n=10A173785
- Numbers that are the sum of three biquadrates (fourth powers) in more than one way.at n=0A193244
- Sophie Germain 5-almost primes.at n=29A211162
- Number of (w,x,y,z) with all terms in {1,...,n} and w<|x-y|+|y-z|.at n=27A212692
- T(n,k)=Number of nXk 0..2 arrays with no more than floor(nXk/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..2 order.at n=46A222986
- Number of 2Xn 0..2 arrays with no more than floor(2Xn/2) elements unequal to at least one horizontal or antidiagonal neighbor, with new values introduced in row major 0..2 order.at n=8A222987
- Smallest number that can be written in exactly n ways as sum of two quarter-squares.at n=17A240952
- Palindromic numbers in bases 6 and 9 written in base 10.at n=15A259389
- Numbers k such that k and k^2 are the sums of two nonzero squares in exactly two ways.at n=33A273293
- a(n) = (2*n^2*(n^2 - 3) - (2*n^2 + 1)*(-1)^n + 1)/64.at n=26A302647
- Numbers k such that 25*10^(2*k) + 5*10^k + 1 are prime.at n=6A308449
- Numbers that are the sum of 3 nonzero 4th powers in more than one way.at n=2A309762