9973
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 9974
- 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
- 9972
- Möbius Function
- -1
- Radical
- 9973
- 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
- 135
- 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
- 1229
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of bipartite partitions of n white objects and 3 black ones.at n=17A000412
- Largest n-digit prime.at n=3A003618
- Bertrand primes: a(n) is largest prime < 2*a(n-1) for n > 1, with a(1) = 2.at n=14A006992
- Numbers whose base-5 representation contains exactly three 3's and two 4's.at n=34A045306
- T(n,n+3), array T as in A047110.at n=7A047118
- Primes whose sum of digits is the perfect number 28.at n=28A048517
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 19.at n=26A050968
- Let prime(i) = i-th prime, let twin(n) = (P,Q) be n-th pair of twin primes; sequence gives prime(P).at n=41A057470
- Prime numbers with odd digits in descending order.at n=32A061245
- Primes with 11 as smallest positive primitive root.at n=40A061324
- Largest n-digit prime with all odd digits.at n=3A068694
- Smallest prime p(k) such that the number of distinct prime divisors of all composite numbers between p(k) and p(k+1) is n.at n=42A075580
- Duplicate of A075580.at n=42A077132
- Smallest prime(k) such that 2^n divides the product of composite numbers between prime(k) and prime(k+1) but 2^(n+1) does not.at n=35A077216
- Smallest prime p such that n applications of f lead form p to 2, where f is the mapping of primes > 2 to primes defined by A052248.at n=14A080190
- Primes p such that (r-p)/log(p) > 3, where r is the next prime after p.at n=26A082888
- Primes whose 10's complement is a cube.at n=5A083018
- a(n) = largest prime using least number of possible digits with a digit sum n, or 0 if no such number exists. E.g., if n > 9 and there are no two-digit primes with a given digit sum n then three-digit numbers are explored and so on.at n=27A088115
- a(n) = prevprime(A090117(n)), the largest prime previous to squares given in A090117, being such that distance of a(n) to the following prime equals 2*n.at n=16A090118
- Primes that represent some mean of 4 consecutive (2 smaller, itself, 1 larger) primes.at n=24A094932