16238
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
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 25488
- Proper Divisor Sum (Aliquot Sum)
- 9250
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7744
- Möbius Function
- -1
- Radical
- 16238
- Omega Function (Ω)
- 3
- 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
- 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
- yes
- Odd
- no
Appears in sequences
- Companion Pell numbers: a(n) = 2*a(n-1) + a(n-2), a(0) = a(1) = 2.at n=11A002203
- Expansion of x^2*(2 - x + x^2) / ((1 + x)*(1 - x)^4).at n=44A026035
- Numbers whose set of base-11 digits is {1,2}.at n=37A032931
- Number of points of L1 norm 3 in cubic lattice Z^n.at n=23A035597
- Coordination sequence for 23-dimensional cubic lattice.at n=3A035718
- Numerators of continued fraction convergents to sqrt(8).at n=10A041010
- Number of 3 X 3 matrices, with elements from {0,...,n}, having the property that the middle element of each of the eight 3-element horizontal, vertical and diagonal lines equals the average of the two end elements.at n=45A059329
- Numbers k such that (k^2 + 4)/2 is a square.at n=5A077444
- Duplicate of A077444.at n=5A077461
- Denominators of continued fraction convergents to zeta(3).at n=9A078985
- a(n) = floor((1+sqrt(2))^n).at n=11A080039
- Start with the sequence S(0)={1,1} and for k>0 define S(k) to be I(S(k-1)) where I denotes the operation of inserting, for i=1,2,3..., the term a(i)+a(i+1) between any two terms for which 4a(i+1)<=5a(i). The listed terms are the initial terms of the limit of this process as k goes to infinity.at n=21A082981
- Partial sums of A084263.at n=45A084570
- Number of subsets of {1,2,...,n} with relatively prime elements.at n=13A085945
- a(1) = 1, a(n) = smallest multiple of n such that the concatenation (n>1) a(n)a(n-1)... a(2) a(1) is a prime.at n=45A089330
- Expansion of (1+x^2)/(1-2*x-x^2).at n=11A099425
- Numbers k such that (2*k)!/(2*(k!)^2) - 1 is prime.at n=25A112861
- Number of ordered triples (i,j,k) in range [0..n] satisfying i == j mod 2 and j == k mod 3.at n=45A115520
- a(n) = -(u^n-1)*(v^n-1) with u = 1+sqrt(2), v = 1-sqrt(2).at n=10A129744
- a(n) = 49*n^2 - 78*n + 31.at n=18A157368