17816
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 35640
- Proper Divisor Sum (Aliquot Sum)
- 17824
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 8320
- Möbius Function
- 0
- Radical
- 4454
- Omega Function (Ω)
- 5
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 141
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- a(n) = prime(n)*prime(n+1) - prime(n).at n=31A037166
- Numbers k such that sigma(k) == 8 (mod k).at n=8A045770
- Numbers k such that k^2 contains exactly 9 different digits.at n=30A054037
- The floor(n^(.9999))-perfect numbers, where f-perfect numbers for an arithmetical function f is defined in A066218.at n=2A066361
- Barely abundant numbers: abundant n such that sigma(n)/n < sigma(m)/m for all abundant numbers m<n, sigma(n) being the sum of the divisors of n.at n=13A071927
- Generalized centered polygonal numbers.at n=15A081282
- An interleaved sequence of pyramidal and polygonal numbers.at n=29A081284
- a(n) = (5*n+1)*(5*n+6).at n=26A085025
- Even and odd solutions to abs(sigma(x)-2x) <= log(x). Numbers n whose abundance-radius does not exceed log(n).at n=38A088011
- Numbers k with abundance radius of 8, i.e., abs(sigma(k)-2*k) = 8.at n=9A088820
- Numbers k whose abundance is 8: sigma(k) - 2*k = 8.at n=4A088833
- Admirable numbers whose abundance is < 10.at n=16A109788
- Admirable numbers such that the subtracted divisor is square.at n=12A109806
- Near-multiperfects with primes excluded, abs(sigma(m) mod m) <= log(m).at n=40A117347
- Near-multiperfects with primes and powers of 2 excluded, abs(sigma(m) mod m) <= log(m).at n=27A117348
- Near-multiperfects with primes, powers of 2 and 6 * prime excluded, abs(sigma(n) mod n) <= log(n).at n=27A117349
- Near-multiperfects with primes, powers of 2, 6 * prime and 2^n * prime excluded, abs(sigma(n) mod n) <= log(n).at n=11A117350
- Location of record values in A080577; also partial sums of A006128 plus 1.at n=20A124920
- Binomial transform of [1, 7, 17, 17, 6, 0, 0, 0, ...].at n=15A132117
- Composite numbers n that divide 2 * sigma(n) - d(n) [that is, 2 * sum of divisors - number of divisors].at n=6A135470