11657
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 11658
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11656
- Möbius Function
- -1
- Radical
- 11657
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 112
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1400
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 61.at n=12A020400
- Primes that remain prime through 3 iterations of function f(x) = 10x + 9.at n=31A023301
- a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+2), with T given by A026120.at n=4A027324
- Primes of the form k^2 - 7.at n=12A028883
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 7.at n=34A031420
- a(n) = prime(100*n).at n=13A031921
- Lower prime of a difference of 20 between consecutive primes.at n=23A031938
- Sort then Add, a(1)=13.at n=11A033897
- Primes p such that x^31 = 2 has no solution mod p.at n=39A059225
- Primes p such that x^47 = 2 has no solution mod p.at n=31A059257
- a(n) = min( x : x^3 + n^3 == 0 mod (x+n-1) ).at n=62A066486
- Primes p such that p+7 == 0 (mod phi(p+7)).at n=25A067606
- Primes arising in A086498: a(n) = (2n)-th partial sum of A086498.at n=35A086499
- Numbers p such that p = (prime(n)+ prime(n+3))/2 is prime for prime indices n=2, 3, 5...at n=16A098039
- Primes of the form pq - 6, where p and q are consecutive primes.at n=13A099775
- First differences of sequence defined in A101172. Also, the Mobius transform of that sequence.at n=15A101173
- Numbers n such that 6*10^n + 4*R_n - 1 is prime, where R_n = 11...1 is the repunit (A002275) of length n.at n=21A103035
- Primes such that the sum of the predecessor and successor primes is divisible by 37.at n=40A113156
- Primes of the form 1+2*n+3*n^2.at n=10A122430
- Primes p such that p - q = 24, where q is the previous prime before p; or prime numbers preceded by precisely 23 composite numbers.at n=16A126720