17157
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 28160
- Proper Divisor Sum (Aliquot Sum)
- 11003
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 9072
- Möbius Function
- 1
- Radical
- 17157
- 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
- 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
- 79
- 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
- Nearest integer to 4 * Pi * n^3 / 3.at n=16A002101
- a(n) = (4*n+1)*(4*n+5).at n=32A003185
- Denominator of (2n+1)(2n+2) B_{2n}, where B_n are the Bernoulli numbers. Also denominators of the asymptotic expansion of the polygamma function psi'''(z).at n=64A006956
- Expansion of 1/((1-2x)(1-4x)(1-5x)(1-7x)).at n=4A025959
- Intermediate edge b of smallest (measured by the longest edge) primitive Euler bricks (a, b, c, sqrt(a^2 + b^2), sqrt(b^2 + c^2), sqrt(a^2 + c^2) are integers).at n=31A031174
- Sums of distinct powers of 7.at n=42A033044
- Base 7 digits are, in order, the first n terms of the periodic sequence with initial period 1,0.at n=5A033117
- Positive numbers having the same set of digits in base 2 and base 7.at n=36A037412
- Sums of 3 distinct powers of 7.at n=14A038482
- Number of partitions satisfying cn(2,5) + cn(3,5) <= cn(1,5) + cn(4,5).at n=37A039895
- Numbers whose base-7 representation has exactly 6 runs.at n=0A043621
- Numbers whose base-5 representation contains exactly three 1's and three 2's.at n=27A045232
- Number of step shifted (decimated) sequences using exactly three different symbols.at n=10A056377
- Number of primitive (aperiodic) step shifted (decimated) sequences using exactly three different symbols.at n=10A056387
- a(n) = floor( (4/3)*Pi*n^3 ).at n=16A066645
- Triangle read by rows: T(n,k), n >=1, 0 <= k <= C(n,k), = number of n X n symmetric positive definite matrices with 2's on the main diagonal and 1's and 0's elsewhere and with k 1's above the diagonal.at n=46A080858
- Symmetric secondary structures of RNA molecules with n nucleotides.at n=24A088518
- a(n) = floor((n+2)^(n+2)/((n+2)^2-1)).at n=5A089815
- Number of irregular primes less than 3^n.at n=11A105458
- Expansion of the solution of a functional equation.at n=14A112482