16625
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
- 16
- Divisor Sum
- 24960
- Proper Divisor Sum (Aliquot Sum)
- 8335
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10800
- Möbius Function
- 0
- Radical
- 665
- 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
- 66
- 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
- A diagonal of A008296.at n=18A059302
- Numbers k such that sigma(sigma(k)) == phi(k) (mod sigma(k)).at n=13A067204
- Numbers k such that (273*2^k+1)^2-2 is prime.at n=27A100914
- Primitive sliding numbers (excludes multiples of 10): totals, including repetitions, of sums r + s, r >= s, such that 1/r + 1/s = (r + s)/10^k for some k >= 0.at n=33A103184
- Numbers k such that 2*prime(k)+1, 2*prime(k+1)+1 and 2*prime(k+2)-1 are also consecutive primes.at n=6A103851
- Numbers n such that 2*P(n)+1, 2*P(n+1)+1, and 2*P(n+2)-1 are also consecutive primes with P(n+1)=P(n)+6 and P(n+2)=P(n+1)+2 with P(i)=i-th prime.at n=5A103852
- Expansion of Product_{k > 0} (1 + A147665(k)*x^k).at n=29A147871
- Numbers k such that sigma(tau(k)) equals the sum of distinct primes dividing k.at n=37A173325
- Number of nX2 0..6 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.at n=2A203060
- Number of nX3 0..6 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.at n=1A203061
- T(n,k)=Number of nXk 0..6 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.at n=7A203066
- T(n,k)=Number of nXk 0..6 arrays with every nonzero element less than or equal to some horizontal or vertical neighbor.at n=8A203066
- Number of (n+1)X(2+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.at n=2A253743
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.at n=8A253749
- Number of (3+1)X(n+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically.at n=1A253751
- Magic sums of 3 X 3 semimagic squares composed of squares.at n=35A265198
- Consider any concatenation of the type n = concat(a,b). Sequence lists numbers that are the sum of the products of some of such couples a and b.at n=27A265737
- Magic sums of 3 X 3 semimagic squares composed of positive squares.at n=32A269061
- Number of irredundant sets in the path graph P_n.at n=17A286887
- a(n) = n^3 * Sum_{p|n, p prime} 1/p^3.at n=49A351242