2393
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2394
- 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
- 2392
- Möbius Function
- -1
- Radical
- 2393
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 71
- 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
- yes
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 356
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/4.at n=17A001134
- Expansion of 1/(1-x)^2/(1-x^2)/(1-x^6)/(1-x^12)/(1-x^24)/(1-x^48)/(1-x^60).at n=42A001365
- Numbers k such that phi(2k-1) < phi(2k), where phi is Euler's totient function A000010.at n=35A001836
- Primes of the form k^2 + k + 41.at n=45A005846
- a(n) = 1 + n/2 + 9*n^2/2.at n=23A006137
- Primes p == 1 (mod 8), p = a^2 + 64*b^2 such that y^2 = x^3 + p*x has rank 2.at n=32A007766
- Coordination sequence T1 for Zeolite Code BRE.at n=32A008058
- Coordination sequence T11 for Zeolite Code MFI.at n=31A008163
- Coordination sequence T2 for Zeolite Code AHT.at n=33A009867
- a(n) = floor(n*(n-1)*(n-2)/15).at n=34A011897
- a(n) is prime and sum of all primes <= a(n) is prime.at n=38A013917
- Primes p == 1 mod 8 such that 2 and -2 are both 4th powers (one implies other) mod p.at n=39A014754
- Seven iterations of Reverse and Add are needed to reach a palindrome.at n=30A015986
- Numbers k such that the continued fraction for sqrt(k) has period 21.at n=18A020360
- Fibonacci sequence beginning 1, 16.at n=12A022106
- n-th prime p(k) such that p(k) + p(k+6) = p(k+2) + p(k+4).at n=41A022891
- Primes that remain prime through 2 iterations of function f(x) = 3x + 8.at n=32A023248
- Right-truncatable primes: every prefix is prime.at n=29A024770
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = A023532, t = (primes).at n=43A025077
- a(n) = (n + 3)^2 - 8.at n=46A028884