12391
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 12392
- 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
- 12390
- Möbius Function
- -1
- Radical
- 12391
- 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
- 63
- 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
- 1479
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Wagstaff numbers: numbers k such that (2^k + 1)/3 is prime.at n=27A000978
- Quintan primes: p = (x^5 + y^5)/(x + y).at n=15A002650
- Primes whose reversal is a square.at n=13A007488
- Smallest prime having least positive primitive root n, or 0 if no such prime exists.at n=25A023048
- Primes that remain prime through 3 iterations of function f(x) = 5x + 6.at n=33A023285
- Primes that remain prime through 3 iterations of function f(x) = 8x + 5.at n=14A023293
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (composite numbers), t = (odd natural numbers).at n=32A024590
- Primes of form 210*p + 1 where p is a prime.at n=11A051648
- Second term of strong prime 5-tuples: p(m)-p(m-1) > p(m+1)-p(m) > p(m+2)-p(m+1) > p(m+3)-p(m+2).at n=31A054809
- Primes p such that x^59 = 2 has no solution mod p.at n=28A059312
- a(n) = floor(exp(Pi*sqrt(n))).at n=9A060456
- Squares of 1 and primes, written backwards.at n=34A060998
- Primes with 26 as smallest positive primitive root.at n=0A061731
- a(n) = floor(e^(n*Pi)).at n=3A062360
- Numbers k such that 2^k + 1 has just two distinct prime factors.at n=47A066263
- Sequence of prime numbers whose reverse is a nontrivial prime power (A025475).at n=10A067194
- Primes whose digit reversal is a nontrivial power.at n=16A069798
- Primes of the form 210n + 1.at n=28A073102
- Numbers k such that 2^k + 1 is the product of two distinct primes.at n=45A073936
- Diagonal of A088262.at n=36A088263