6199
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 6200
- 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
- 6198
- Möbius Function
- -1
- Radical
- 6199
- 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
- 137
- 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
- 806
- 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 even period and if the last term of the periodic part is deleted the central term is 77.at n=20A031575
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 58 ones.at n=4A031826
- Numbers having four 4's in base 5.at n=30A043368
- Primes with first digit 6.at n=40A045712
- Lower members of a "good pair" of the form (k, 2*k +- 1).at n=42A046861
- Primes that yield a different prime when rotated by 180 degrees.at n=21A048890
- Expansion of (1-x)/(1 - 3*x - x^2 + 2*x^3).at n=8A052911
- Numbers n such that n^2 contains exactly 8 different digits.at n=41A054036
- The primes in A045574.at n=41A057770
- a(n) = ceiling(log(n)*exp(n)).at n=7A058751
- a(n) = round(log(n)*exp(n)).at n=7A058752
- Numbers k such that k! - prime(k) is prime.at n=31A064401
- Smallest prime whose decimal expansion ends (nontrivially) with the n-th prime; or 0 if no such prime exists.at n=45A065112
- Middle members of prime triples {p, p+2, p+6}.at n=45A073648
- Numbers k such that sigma(k) is a harmonic number.at n=30A074245
- Primes p such that p + 4 is prime and p == 9 (mod 10).at n=43A074822
- Primes p such that the number of distinct prime divisors of all composite numbers between p and the next prime is 8.at n=43A075588
- Primes that are still primes when turned upsided down.at n=25A080788
- Numbers k such that Fibonacci(k) concatenated with its 10's complement is prime.at n=23A084621
- p(k) such that 2*p(k)+3 and 2*p(k+1) + 3 are consecutive primes, where p(i) denotes the i-th prime.at n=28A089527