16601
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17892
- Proper Divisor Sum (Aliquot Sum)
- 1291
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15312
- Möbius Function
- 1
- Radical
- 16601
- 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
- 40
- 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
- Numbers k such that 221*2^k+1 is prime.at n=36A032487
- Trajectory of n under the Reverse and Add! operation carried out in base 2 does not reach a palindrome and (presumably) does not join the trajectory of any term m < n.at n=35A075252
- Diagonal in array of n-gonal numbers A081422.at n=25A081435
- a(n) = smallest k such that the base-2 Reverse and Add! trajectory of A075252(n) joins the trajectory of k.at n=35A092211
- a(n) = A108462(A025487(n)).at n=19A108463
- Beach-Williams Pell numbers of type pq (p,q primes).at n=14A212078
- Expansion of (1-q)^k/Product_{j=1..k} (1-q^j) for k=12.at n=38A275643
- a(n) = (n+1)*(n^4-4*n^3+11*n^2-8*n+12)/12.at n=12A302612
- Sum of the third largest parts of the partitions of n into 5 parts.at n=48A308825
- Array read by upwards antidiagonals: T(m,n) = number of set partitions of the multiset consisting of one copy each of x_1, x_2, ..., x_m, and two copies each of y_1, y_2, ..., y_n, for m >= 0, n >= 0.at n=25A322765
- Row 2 of array in A322765.at n=4A322767
- Values of w(k) when w(k-2), w(k-1), and w(k) are all odd, where w is A336957.at n=4A338071
- Number of partitions of the (n+4)-multiset {1,2,...,n,1,2,3,4}.at n=6A346881
- Number of partitions of the (n+6)-multiset {1,2,...,n,1,2,...,6}.at n=4A346883
- a(n) is the smallest number which can be represented as the sum of n distinct nonzero squares in exactly n ways, or 0 if no such number exists.at n=34A350241
- Number of achiral hexagonal polyominoes with 3n cells and threefold rotational symmetry centered at a vertex.at n=14A350243