3191
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 3192
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3190
- Möbius Function
- -1
- Radical
- 3191
- 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
- 74
- 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
- 452
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes of the form k^2 - k - 1.at n=32A002327
- Smallest number with reciprocal of period length n in decimal (base 10).at n=29A003060
- a(n) = solution to the postage stamp problem with n denominations and 9 stamps.at n=6A005344
- Smallest primitive factor of 10^n - 1. Also smallest prime p such that 1/p has repeating decimal expansion of period n.at n=28A007138
- Primes of form 3*k^2 - 3*k + 23.at n=28A007637
- Numbers k such that (3^k + 1)/4 is prime.at n=13A007658
- Expansion of (1+x^2)(1+x^4)/((1-x)^2*(1-x^2)*(1-x^3)).at n=30A007979
- Coordination sequence T4 for Zeolite Code MTW.at n=37A008199
- Crystal ball sequence for A_10 lattice.at n=2A008396
- Expansion of 1/((1-2*x)*(1-6*x)*(1-11*x)).at n=3A016308
- Numbers k such that the continued fraction for sqrt(k) has period 36.at n=40A020375
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t = A002808 (composite numbers).at n=27A023863
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (composite numbers).at n=26A024860
- Numbers whose least quadratic nonresidue (A020649) is 11.at n=18A025024
- Index of 7^n within the sequence of the numbers of the form 2^i*7^j.at n=47A025720
- Chebyshev even-indexed U-polynomials evaluated at sqrt(7)/2.at n=5A030221
- Primes which when concatenated with next 3 primes are also prime.at n=29A030472
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 55.at n=16A031553
- Lower prime of a difference of 12 between consecutive primes.at n=31A031930
- Primes of form x^2 + 94*y^2.at n=26A033204