13397
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
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 13398
- 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
- 13396
- Möbius Function
- -1
- Radical
- 13397
- 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
- 45
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1588
- 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 63.at n=19A020402
- Let (p1,p2), (p3,p4) be pairs of twin primes with p1*p2=p3+p4-1; sequence gives values of p1.at n=17A047976
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 19.at n=31A050968
- Integers n > 1997 such that the 'Reverse and Add!' trajectory of n joins the trajectory of 1997.at n=28A063055
- Primes p such that the number of distinct prime divisors of all composite numbers between p and the next prime is 5.at n=22A075585
- a(n) = (4*7^n + (-3)^n)/5.at n=5A083300
- Smaller member of a twin prime pair with a triangular sum.at n=10A086816
- Smallest member of a pair of consecutive twin prime pairs that have exactly n primes between them.at n=25A089637
- Primes prime(k) such that (prime(k-1) + prime(k+1) + prime(k+2))/prime(k) = 3.at n=24A094933
- a(n) = n for n <= 2; for n > 2, a(n) = 2a(n-1) - a(n - floor( 1/2 + sqrt(2n) )).at n=17A096796
- Primes from merging of 5 successive digits in decimal expansion of exp(Pi).at n=30A105010
- Primes p such that p + 2 and p^2 + 2^2 are primes.at n=27A107312
- Primes p such that p's set of distinct digits is {1,3,7,9}.at n=7A108386
- Lesser of twin primes for which the gap before the following twin primes is a record.at n=10A113275
- Numerators of partial alternating sums of Catalan numbers scaled by powers of 1/5.at n=6A121006
- Primes of the form 256 k + 85.at n=14A127593
- Primes in A023108(n); or Lychrel primes.at n=33A135316
- Lesser of twin primes isolated from neighboring primes by +- 10 (or more).at n=25A138063
- Primes congruent to 24 mod 43.at n=36A142273
- Primes congruent to 2 mod 47.at n=30A142355