6627
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 9028
- Proper Divisor Sum (Aliquot Sum)
- 2401
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4324
- Möbius Function
- 0
- Radical
- 141
- Omega Function (Ω)
- 3
- 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
- 93
- 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
- no
- Odd
- yes
Appears in sequences
- Sum of logarithmic numbers.at n=6A002746
- a(n)-th prime is sum of first k primes for some k.at n=19A020641
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 27.at n=30A031525
- Number of partitions of n with equal nonzero number of parts congruent to each of 0 and 1 (mod 3).at n=45A035537
- Numbers m such that there are precisely 3 groups of order m.at n=32A055561
- Numbers k such that k^2 + k + 1, k^3 + k + 1 and k^4 + k + 1 are all prime.at n=26A057683
- Numbers k such that phi(k) mod core(k) = 1 where core(k) is the squarefree part of k.at n=43A069946
- G.f.: Sum_{n >= 1} x^n/(1-x^n)^5.at n=17A073570
- 3p^2 where p runs through the primes.at n=14A079705
- Numbers k such that 30*k+{1,7,13,17,19,23,29} are all prime.at n=1A100419
- First trisection of A061040.at n=46A147650
- Number of triangles that can be built from rods with lengths 1,2,...,n by using and concatenating all rods.at n=30A160455
- Number of digits in n-th even perfect number written in base 8.at n=21A161514
- Odd numbers k such that A166100((k-1)/2)/k is not an integer.at n=14A166102
- Integers whose binary digits "1" define, if sorted into a quadrant shape whose right angle lies in a Go board corner, same colored Go stones that surely live all, but not if any stone is omitted.at n=13A166537
- Numbers of the form 20*k+7 which are three times a square.at n=9A192328
- Number of 0..3 arrays x(0..n-1) of n elements with each no smaller than the sum of its three previous neighbors modulo 4.at n=8A200663
- Numbers congruent to 3 in the structure (or curve) of A211000.at n=40A211002
- 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=19A212481
- Number of n X 2 0..3 arrays with successive rows and columns fitting to straight lines with nondecreasing slope, with a single point array taken as having zero slope.at n=3A223069