16207
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17080
- Proper Divisor Sum (Aliquot Sum)
- 873
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15336
- Möbius Function
- 1
- Radical
- 16207
- 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
- 190
- 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
- Tetranacci numbers: a(n) = a(n-1) + a(n-2) + a(n-3) + a(n-4), with a(0)=a(1)=0, a(2)=1, a(3)=2.at n=17A001630
- Number of sensed planar maps with n edges and without faces or vertices of degree 1.at n=10A006396
- a(n) = Sum_{k=0..n-1} T(n,k) * T(n,2n-k), with T given by A027082.at n=7A027105
- a(n) = (n + 2)*(2*n^2 - n + 3)/6.at n=36A056520
- Average of four successive primes squared, (prime(n)^2 + prime(n+1)^2 + prime(n+2)^2 + prime(n+3)^2)/4, n>=2.at n=28A075894
- Numbers k such that floor(10^k * Pi) is prime.at n=4A094875
- Semiprimes in A003215.at n=30A113530
- Numbers n such that one of floor(10^n * Pi) or ceiling(10^n * Pi) is prime.at n=11A140515
- a(n) = 12*n^2 + 18*n + 7.at n=36A154105
- Cuban composites: composite numbers equal to the difference of two consecutive cubes.at n=39A159961
- Potential magic constants of 9 X 9 magic squares composed of consecutive primes.at n=28A191679
- Number of nondecreasing sequences of n 1..7 integers with every element dividing the sequence sum.at n=30A212535
- Integers n such that appending some decimal digit to the first n digits of Pi results in a prime.at n=30A231336
- 25-gonal numbers: a(n) = n*(23*n-21)/2.at n=38A255184
- Modified quadranacci series.at n=47A274759
- Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 331", based on the 5-celled von Neumann neighborhood.at n=13A281178
- Expansion of Product_{k>=1} (1 + x^k)^A007437(k).at n=12A301874
- a(n) = Sum_{k=1..n} (k/gcd(n, k))^2.at n=36A332654
- Number of palindromic binary strings of length n having no 4-runs of 1's.at n=30A382478