8407
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
- 4
- Divisor Sum
- 9616
- Proper Divisor Sum (Aliquot Sum)
- 1209
- 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
- 7200
- Möbius Function
- 1
- Radical
- 8407
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 65
- 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(0) = 1, a(n) = 5*n^2 + 2 for n>0.at n=41A010001
- a(n)-th prime is sum of first k primes for some k.at n=21A020641
- a(n) = (n/2)*(n^4 + 1).at n=7A021003
- Numbers k such that Fib(k) == 13 (mod k).at n=38A023178
- Expansion of sum ( q^n / product( 1-q^k, k=1..4*n), n=0..inf ).at n=27A035296
- Number of partitions of n such that cn(3,5) <= cn(0,5) = cn(1,5) < cn(2,5) = cn(4,5).at n=72A036868
- The terms of A055258 (sums of two powers of 7) divided by 2.at n=16A073218
- Numbers k such that (13*10^(k-1) - 31)/9 is a plateau prime.at n=3A082698
- (1/4)*number of non-degenerate isosceles triangles that can be formed from the points of an (n+1)X(n+1)X(n+1) lattice cube.at n=3A103500
- Triangle read by rows: T(n,k) = n*(1+n^k)/2, 0<=k<=n.at n=32A108396
- Numbers n such that 99 * 10^n + 1 is prime.at n=16A109713
- Members of 3-cycles of permutation A111273.at n=6A113701
- Numbers k such that 10*(10^(k+1) + 10^k - 1) + 7 is prime.at n=19A123368
- Number of ways, counted up to symmetry, to build a contiguous building with n LEGO blocks of size 1 X 2 which is flat, i.e., with all blocks in parallel position.at n=7A123764
- A Fibonacci-based recurrence.at n=21A139759
- a(n) is the smallest natural number we cannot obtain from n, n+1, n+2, n+3, n+4, n+5, n+6 and the operators +, -, *, /, using each number only once.at n=10A143191
- Half the number of n X n X n triangular binary arrays with no array-aligned 2 X 2 X 2 subtriangle being all zero or all one.at n=5A183278
- E.g.f. A(x) satisfies: A(x) = cosh(x*A(x)) + sin(x*A(x)).at n=6A195134
- T(n,k)=Number of nXk 0..1 arrays with row sums nondecreasing and column sums unimodal.at n=46A223625
- Number of 2Xn 0..1 arrays with row sums nondecreasing and column sums unimodal.at n=8A223626