16771
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17344
- Proper Divisor Sum (Aliquot Sum)
- 573
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16200
- Möbius Function
- 1
- Radical
- 16771
- 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
- 66
- 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 that are the sum of 7 positive 7th powers.at n=39A003374
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 66 ones.at n=27A031834
- Numbers whose base-7 representation contains exactly four 6's.at n=19A043420
- a(n) = 9*n^2 + 3*n + 1.at n=43A082040
- Composite numbers such that all divisors >1 have the same number of 1's in binary representation.at n=35A089042
- Expansion of 1/(1 - (x + x^2)c(3x)), c(x) the g.f. of A000108.at n=6A110521
- Number of 3-almostprimes <= 2^n.at n=15A127396
- Number of nodes (or order) of a graph model obtained using an automata scheme on sets of order prime(n) >= 5 and in which all not halt states are linked by arcs (edges).at n=29A160772
- Wiener index of the n-sunlet graph.at n=28A180574
- Number of (n+1) X 9 binary arrays with each element of every 2 X 2 subblock being the sum mod 2 of two others.at n=0A183844
- T(n,k)=Number of (n+1)X(k+1) binary arrays with each element of every 2X2 subblock being the sum mod 2 of two others.at n=28A183845
- T(n,k)=Number of (n+1)X(k+1) binary arrays with each element of every 2X2 subblock being the sum mod 2 of two others.at n=35A183845
- Number of decompositions of highly composite numbers (A002182) into unordered sums of two primes.at n=38A228943
- Least number k > 0 such that k*2^n+1 is a cube.at n=7A239679
- Least integer k such that the n-th prime of form m^2+1 divides the composite number k^2+1.at n=24A255675
- Numbers k with the property that it is possible to write the base 2 expansion of k as concat(a_2,b_2), with a_2>0 and b_2>0 such that, converting a_2 and b_2 to base 10 as a and b, we have sigma(a) + sigma (b) = sigma(k) - k.at n=27A258813
- 38-gonal numbers: a(n) = n*(18*n-17).at n=31A282850
- Digits of the Copeland-Erdős constant taken in groups of five digits.at n=31A304652
- Replacing each digit d in decimal expansion of n with d^2 yields a prime at each step when done recursively three times.at n=20A316604
- Odd composite integers m such that A014448(m) == 4 (mod m).at n=33A335670