16254
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 42240
- Proper Divisor Sum (Aliquot Sum)
- 25986
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4536
- Möbius Function
- 0
- Radical
- 1806
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 190
- 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
- a(n) = (5*n+1)*(5*n+4).at n=25A001545
- Numbers k such that k divides 2^(k+1) - 2.at n=40A014741
- Positive integers n such that n | (2^n + n/2 - 1).at n=38A015942
- Number of aperiodic binary strings of length n; also number of binary sequences with primitive period n.at n=14A027375
- Row sums of triangle T(m,n) = number of solutions to 1 <= a(1) < a(2) < ... < a(m) <= n, where gcd(a(1), a(2), ..., a(m), n) = 1, in A020921.at n=13A038199
- Gaps of 9 in sequence A038593 (lower terms).at n=12A038657
- Gaps of 9 in sequence A038593 (upper terms).at n=11A038658
- Numbers ending with '4' that are the difference of two positive cubes.at n=34A038859
- Number of primitive (aperiodic) words of length n which contain exactly two different symbols.at n=13A056267
- Number of primitive (aperiodic) palindromes using a maximum of two different symbols.at n=27A056458
- Number of primitive (aperiodic) palindromes using exactly two different symbols.at n=27A056463
- Engel expansion of sinh(1/3).at n=21A068380
- Number of triangles similar to their n-th pedal, and not similar to any k-th pedal for k < n.at n=6A102536
- Number of squares in the interior of the square with vertices (n,0), (0,n), (-n,0) and (0,-n) in a square (x,y)-grid.at n=28A111746
- Number of 5-way intersections in the interior of a regular 6n-gon.at n=42A137939
- a(n) = 1 if a(n-1) is prime, otherwise a(n-1) + a(n-2), with a(0) = 0 and a(1) = 1.at n=47A142878
- Triangle read by rows: expansion of p(x,n)=If[n == 0, 1, (x + 1)^n + 2^(n - 3)*Sum[Binomial[n, m]*x^m*(1 + x^(n - 2*m)), {m, 1, n - 1}]].at n=49A146767
- Triangle read by rows: expansion of p(x,n)=If[n == 0, 1, (x + 1)^n + 2^(n - 3)*Sum[Binomial[n, m]*x^m*(1 + x^(n - 2*m)), {m, 1, n - 1}]].at n=50A146767
- a(n) = 9*n*(n+1).at n=42A163758
- a(n) = 4^n-2^n-2.at n=6A170940