6670
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 12960
- Proper Divisor Sum (Aliquot Sum)
- 6290
- 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
- 2464
- Möbius Function
- 1
- Radical
- 6670
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- yes
- 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
- 181
- 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
- Number of atoms in a decahedron with n shells.at n=20A004068
- a(n) = 2*n*(4*n - 1).at n=29A014635
- Values of A038007 not ending in 6 or 8.at n=7A038009
- Numbers whose base-9 representation has exactly 5 runs.at n=17A043634
- Values of m, the main key or generating number for Pythagorean triangles in which S (the odd short leg) and U (the hypotenuse) are twin primes.at n=29A051891
- Centered 9-gonal (also known as nonagonal or enneagonal) numbers. Every third triangular number, starting with a(1)=1.at n=38A060544
- a(n) = 49*(n*(n+1)/2) + 6.at n=16A061792
- Centered 19-gonal numbers.at n=26A069132
- Triangular numbers of the form 10*k.at n=22A069498
- a(1)=1; a(n) = a(n-1) + [sum of all decimal digits present so far in the sequence].at n=35A072921
- z-value of the solution (x,y,z) to 5/n = 1/x + 1/y + 1/z satisfying 0 < x < y < z and having the largest z-value. The x and y components are in A075249 and A075250.at n=20A075251
- Sums of groups in A075643.at n=21A075645
- Triangular numbers which are 4-almost primes.at n=31A076578
- Smaller of the two successive triangular numbers which differ in the use of only one digit.at n=26A077759
- a(n) = (2*n^3 - n^2 - n + 2)/2.at n=19A081441
- Antidiagonal sums of square array A082025.at n=22A082190
- a(n) = A052217(n)/3.at n=31A088405
- Fourth column (m=3) of (1,6)-Pascal triangle A096956.at n=28A096957
- Number of unlabeled (and unrooted) trees on 2n nodes with a bicentroid.at n=8A102911
- a(n) is the sum of entries of n-th Kostka matrix for the partitions of n.at n=9A104779