4013
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 8
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 4014
- 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
- 4012
- Möbius Function
- -1
- Radical
- 4013
- 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
- 43
- 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
- 554
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Spiral sieve using Fibonacci numbers.at n=17A005624
- Number of factorization patterns of polynomials of degree n over F_2.at n=21A006167
- Balanced primes (of order one): primes which are the average of the previous prime and the following prime.at n=33A006562
- Numbers k such that the continued fraction for sqrt(k) has period 19.at n=27A020358
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = (composite numbers).at n=22A024588
- Number of 4's in all partitions of n.at n=29A024788
- 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=29A024860
- 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 9.at n=9A031422
- Binomial transform of A002054.at n=5A034942
- n! has a palindromic prime number of digits.at n=16A035067
- Coordination sequence T3 for Zeolite Code AFN.at n=45A038401
- Coordination sequence T13 for Zeolite Code STT.at n=42A038420
- Denominators of continued fraction convergents to sqrt(175).at n=6A041323
- Denominators of continued fraction convergents to sqrt(700).at n=10A042347
- Primes with first digit 4.at n=23A045710
- Third member of a sexy prime quadruple: value of p+12 such that p, p+6, p+12 and p+18 are all prime.at n=16A046123
- Primes p such that p+6 and p+8 are also primes.at n=32A046138
- p, p+6 and p+8 are all primes (A046138) but p+2 is not.at n=22A049438
- a(n) = Sum_{i=0..2n} (-1)^i * T(i,2n-i), array T as in A049735.at n=18A049737
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 17.at n=9A050966