5623
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 5624
- 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
- 5622
- Möbius Function
- -1
- Radical
- 5623
- 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
- 59
- 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
- 739
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Smallest prime p such that there is a gap of 2n between p and previous prime.at n=15A001632
- a(n) = 3 + n/2 + 7*n^2/2.at n=40A006124
- Where the prime race among 5k+1, ..., 5k+4 changes leader.at n=29A007353
- If x and y are terms, so is x*y + 9.at n=32A009350
- Powers of fourth root of 10 rounded down.at n=15A018072
- Powers of fourth root of 10 rounded to nearest integer.at n=15A018073
- Smallest nonempty set S containing prime divisors of 5k+8 for each k in S.at n=25A020600
- Smallest nonempty set S containing prime divisors of 9k+5 for each k in S.at n=27A020627
- Primes of the form k^2 - 2.at n=22A028871
- 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 73.at n=25A031571
- Lower prime of a pair of consecutive primes having a difference of 16.at n=18A031934
- a(n) is square mod a(i), i < n; a(n) prime; a(1) = 2.at n=9A034900
- Primes with indices that are primes with prime indices.at n=31A038580
- Numbers whose base-7 representation contains exactly four 2's.at n=16A043404
- Numbers whose base-4 representation contains exactly four 1's and three 3's.at n=2A045132
- Numbers whose base-5 representation contains exactly two 3's and three 4's.at n=13A045303
- Prime islands: for n >= 2, a(n) = least prime whose adjacent primes are exactly 2n apart; a(1) = 3 by convention.at n=23A046931
- Primes prime(k) for which A049076(k) = 3.at n=20A049079
- a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 2 and a(3) = 4.at n=13A049914
- Fifth term of weak prime quintets: p(m-3)-p(m-4) < p(m-2)-p(m-3) < p(m-1)-p(m-2) < p(m)-p(m-1).at n=13A054827