6447
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
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 9856
- Proper Divisor Sum (Aliquot Sum)
- 3409
- 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
- 3672
- Möbius Function
- -1
- Radical
- 6447
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 75
- 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
- no
- Odd
- yes
Appears in sequences
- Mixed partitions of n.at n=30A002096
- Expansion of 1/((1-4x)(1-6x)(1-8x)(1-9x)).at n=3A028135
- Lucky numbers with size of gaps equal to 16 (lower terms).at n=20A031898
- Number of partitions satisfying (cn(0,5) <= cn(1,5) = cn(4,5) and cn(0,5) <= cn(2,5) and cn(0,5) <= cn(3,5)).at n=47A036813
- Denominators of continued fraction convergents to sqrt(201).at n=12A041373
- Denominators of continued fraction convergents to sqrt(804).at n=8A042551
- Prime(prime(n)) ends with n.at n=0A074978
- Triangle T(n,k) read by rows: permutations on 123...n with one abc pattern and no aj pattern with j<=k, n>2, k<n-1.at n=30A084249
- Expansion of (1-3x)/((1-x)(1-4x)(1-5x)).at n=5A097165
- Indices of primes in sequence defined by A(0) = 91, A(n) = 10*A(n-1) + 11 for n > 0.at n=13A101001
- Triangle T, read by rows, that satisfies: T(n,k) = [T^3](n-1,k) for n>k+1>=1, with T(n,n) = 1 and T(n+1,n) = n+1 for n>=0, where T^3 is the matrix cube of T.at n=21A109282
- Column 0 of triangle A109282.at n=6A109283
- n(k) is the minimum number that require at least k to make Prime[n]+2*Prime[n+k] a prime.at n=44A114264
- Number of n X n binary arrays symmetric under 90 degree rotation with all ones connected only in a 5-point barb 1,1 1,2 2,2 2,3 3,2 in any orientation.at n=11A146142
- Triangle T(n, k, j) = T(n-1, k, j) + T(n-1, k-1, j) + (2*j + 1)*prime(j)*T(n-2, k-1, j) with T(2, k, j) = prime(j) and j = 7, read by rows.at n=22A153652
- Triangle T(n, k, j) = T(n-1, k, j) + T(n-1, k-1, j) + (2*j + 1)*prime(j)*T(n-2, k-1, j) with T(2, k, j) = prime(j) and j = 7, read by rows.at n=26A153652
- Nonprimes formed by concatenation of the decimal digits of a nonprime and its index.at n=39A154507
- a(n) = 343*n - 70.at n=18A157374
- a(n) = 13*n^2 + 7*n + 1.at n=21A168240
- n such that the Moebius function take successively, from n, the values -1,0,-1,0,-1,0.at n=27A172354