5087
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 5088
- 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
- 5086
- Möbius Function
- -1
- Radical
- 5087
- 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
- 178
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 680
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes p == 7, 19, 23 (mod 40) such that (p-1)/2 is also prime.at n=35A000353
- a(n) = floor(1000*log_2(n)).at n=33A004265
- a(n) = round(1000*log_2(n)).at n=33A004266
- Primes that remain prime through 2 iterations of the function f(x) = 2x + 7.at n=46A023244
- Number of T-frame polyominoes with n cells.at n=42A028247
- 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 71.at n=3A031569
- a(1) = 1; a(n) is smallest number >= a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=40A033680
- Number of symmetric n X 4 crossword puzzle grids.at n=7A034186
- Decimal part of n^(1/11) starts with a 'nine digits' anagram.at n=0A034286
- Decimal part of a(n)^(1/n) starts with a 'nine digits' anagram.at n=9A035136
- Primes which are not the sum of consecutive composite numbers.at n=28A037174
- Denominators of continued fraction convergents to sqrt(261).at n=8A041489
- Numbers whose base-4 representation contains exactly two 1's and four 3's.at n=17A045123
- Primes with first digit 5.at n=27A045711
- Primes p such that pp'-2 is prime, where p' denotes the next prime after p.at n=28A048797
- Smaller term of closest safe prime pairs.at n=10A059323
- Special safe primes (from A005385) such that the next prime is also a safe prime.at n=5A059394
- Smaller of safe prime twins: special safe primes (A005385) p such that the next prime is also the next safe prime and is p+12, i.e., occurs at the closest possible distance, 12.at n=3A059395
- Denoting 4 consecutive primes by p, q, r and s, these are the values of q such that q and r have 10 as a primitive root, but p and s do not.at n=39A060259
- Primes p for which the exponent of the highest power of 2 dividing p! is equal to prevprime(prevprime(p)).at n=19A064396