6731
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6912
- Proper Divisor Sum (Aliquot Sum)
- 181
- 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
- 6552
- Möbius Function
- 1
- Radical
- 6731
- 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
- 44
- 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
- a(n) = floor( n*(n-1)*(n-2)/11 ).at n=43A011893
- Fibonacci sequence beginning 3, 16.at n=14A022126
- Convolution of odd numbers and A000201.at n=22A023658
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 15 ones.at n=5A031783
- Denominators of continued fraction convergents to sqrt(926).at n=8A042791
- Numbers n such that 1n1, 3n3, 7n7 and 9n9 are all primes.at n=14A059677
- Total number of odd parts in all partitions of n.at n=22A066897
- Number of partitions of n such that the set of odd parts has only one element.at n=45A090868
- a(n) = 6*n*(n-1) - 1.at n=34A103115
- Least multiple of prime(n) ending in digits of n.at n=27A114012
- Increasing gaps in the even sieve (A056533) by lower term.at n=16A119503
- Numbers k such that 1 + k + k^3 + k^5 + k^7 + k^9 + k^11 + ... + k^61 + k^63 is prime.at n=43A124209
- an=n-th smallest integer of the form m=p1*p2 where pi are odd primes such that d+2m/d are all primes for d dividing 2m.at n=43A128279
- a(n) = 30*n^4 - 120*n^3 + 120*n^2 - 19.at n=5A157411
- a(1)=1. a(n) = the smallest integer > a(n-1) that is an (odd) palindrome when written in binary, and is such that (a(n)-a(n-1))/2 is prime.at n=16A161536
- Row sums of triangular table A138612.at n=13A166020
- One third of product plus sum of six consecutive nonnegative numbers.at n=3A166943
- a(n) = Fibonacci(n+9) - Fibonacci(9).at n=11A180674
- Number of nondecreasing arrangements of n+2 numbers in 0..6 with the last equal to 6 and each after the second equal to the sum of one or two of the preceding three.at n=41A190038
- a(n) = prime(n) * prime(2*n-1).at n=15A219603