6319
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6480
- Proper Divisor Sum (Aliquot Sum)
- 161
- 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
- 6160
- Möbius Function
- 1
- Radical
- 6319
- 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
- 199
- 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
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=39A007697
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=41A007697
- Smallest odd number expressible in at least n ways as p+2*m^2 where p is 1 or a prime and m >= 0.at n=40A007697
- Consider all ways of writing a number as p+2m^2 where p is 1 or a prime and m >= 0; sequence gives numbers that are expressible in at least 2 more ways than any smaller number.at n=8A016067
- a(n) = 9*a(n - 1) - a(n - 2) for n>1, a(0)=0, a(1)=1.at n=5A018913
- 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 79.at n=10A031577
- Number of partitions satisfying cn(0,5) + cn(2,5) + cn(3,5) < cn(1,5) + cn(4,5).at n=33A039881
- Denominators of continued fraction convergents to sqrt(77).at n=9A041137
- Denominators of continued fraction convergents to sqrt(308).at n=9A041581
- n-th 4k+1 prime times (n+1)st 4k+3 prime.at n=9A048628
- Smallest integer that can be expressed as p+2m^2 in more ways than any smaller number, where m >= 0 and p = 1 or prime.at n=29A055202
- a(n) = n^4 - 3*n^2 + 1.at n=9A057722
- a(n) = least odd number which can be represented in the form p + 2*k^2, k>0, in n different ways.at n=42A060004
- Numbers k such that k*2^m+1 is prime for exactly one exponent m in the range 0<=m<=k.at n=44A061155
- Potential Sierpiński numbers: integers for which the smallest m > 2^10 in A040076 such that n*2^m+1 is prime (A050921).at n=21A064721
- Centered 18-gonal numbers.at n=26A069131
- Nonprime numbers k such that (k+1)*Sum_{d|k} 1/(d+1) is an integer.at n=11A069155
- Duplicate of A069155.at n=11A074977
- a(n) = 4*n^2 + 6*n + 1.at n=39A082108
- Numbers n such that A003313(n) = A003313(2n).at n=18A086878