6637
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 6638
- 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
- 6636
- Möbius Function
- -1
- Radical
- 6637
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 44
- 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
- 856
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Crystal ball sequence for A_7 lattice.at n=3A008390
- Numbers k such that the continued fraction for sqrt(k) has period 37.at n=15A020376
- Primes that remain prime through 3 iterations of function f(x) = 5x + 6.at n=25A023285
- Lower prime of a pair of consecutive primes having a difference of 16.at n=20A031934
- Upper prime of a difference of 18 between consecutive primes.at n=26A031937
- Primes p such that (p+1)/2 and (p+2)/3 are also primes.at n=18A036570
- T(n,n), array T as in A047100.at n=8A047102
- a(n) = A047980(2n).at n=31A047981
- n plus a googol is prime.at n=19A049014
- Least prime in A031934 (lesser of 16-twins) whose distance to the next 16-twin is 6*n.at n=18A052357
- Prime number spiral (clockwise, North spoke).at n=15A054551
- Second term of strong prime 5-tuples: p(m)-p(m-1) > p(m+1)-p(m) > p(m+2)-p(m+1) > p(m+3)-p(m+2).at n=17A054809
- Primes p such that |p - q| is a square, where q is the reversal of p.at n=21A059798
- a(n) = Sum_{i=1..n} floor((3/2)^i).at n=18A066778
- Prime(n) and prime(n+4) use the same digits.at n=7A069796
- A sequence of primes such that {a(n)-a(n-1)}/{a(n-1)-a(n-2)} is a unique integer.at n=8A084761
- Primes of the form k^2 - 7*k + 7.at n=21A089376
- Greatest number in the n-th successive group of natural numbers containing exactly n prime powers.at n=41A092463
- Primes p such that both the digit sum of p plus p and the digit product of p plus p are also primes.at n=24A092529
- Table of crystal ball sequences for A_n lattices read by antidiagonals.at n=62A099608