16662
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 33336
- Proper Divisor Sum (Aliquot Sum)
- 16674
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 5552
- Möbius Function
- -1
- Radical
- 16662
- 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
- 159
- 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
- Numbers whose base-4 representation contains exactly three 0's and four 1's.at n=28A045032
- Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion.at n=27A051003
- Number of Hamiltonian paths in the graph on n vertices {1,...,n}, with i adjacent to j iff |i-j| <= 2.at n=23A069241
- Numbers k such that k and k^2 use only the digits 1, 2, 4, 6 and 7.at n=27A136993
- Indices k such that A019326(k)=Phi[k](8) is prime, where Phi is a cyclotomic polynomial.at n=31A138938
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, 0), (-1, 1, 0), (0, 0, 1), (1, 1, -1)}.at n=10A148438
- 1/4 the number of (n+1) X 6 binary arrays with all 2 X 2 subblock sums the same.at n=14A183982
- Least k such that k*6^n-1 , k*6^n+1, and 2*k*6^n-1 are prime; that is, twin primes and a Sophie Germain prime.at n=34A212481
- Periods associated with A217611.at n=34A217646
- Number of partitions of n with difference 2 between the number of odd parts and the number of even parts, both counted without multiplicity.at n=42A242693
- Number of n X 2 0..2 arrays with no element unequal to a strict majority of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards.at n=9A279866
- Number of 2 X 2 matrices with all elements in 0..n such that the sum of the elements is prime.at n=15A281550