1591
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1672
- Proper Divisor Sum (Aliquot Sum)
- 81
- 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
- 1512
- Möbius Function
- 1
- Radical
- 1591
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 104
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers that are the sum of 9 positive 6th powers.at n=21A003365
- a(n) = 1000*log_10(n) rounded to the nearest integer.at n=38A004226
- Representation degeneracies for boson strings.at n=24A005292
- Coordination sequence T1 for Zeolite Code iRON.at n=28A009881
- a(n) = prevprime(n)*nextprime(n).at n=38A013638
- Number of ordered quadruples of integers from [ 1,n ] with no common factors between pairs.at n=22A015636
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite CON = CIT-1 H2[B2Si54O112] starting with a T7 atom.at n=10A019097
- Pseudoprimes to base 36.at n=18A020164
- Pseudoprimes to base 85.at n=23A020213
- Strong pseudoprimes to base 85.at n=3A020311
- Numbers k such that the continued fraction for sqrt(k) has period 32.at n=21A020371
- Triangle of Gaussian binomial coefficients [ n,k ] for q = 6.at n=12A022170
- Gaussian binomial coefficients [ n,2 ] for q = 6.at n=2A022220
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (composite numbers), t = (primes).at n=12A024604
- a(n) = position of 2*n^3 in A003325.at n=47A024667
- Number of partitions of n into an odd number of parts, the least being 5; also, a(n+5) = number of partitions of n into an even number of parts, each >=5.at n=61A027191
- Number of distinct products ijk with 0 <= i < j < k <= n.at n=30A027429
- a(n) = n*(n + 6).at n=37A028560
- For n>0, a(n) is the least quasi-Carmichael number to base n; a(0) = least composite squarefree integer.at n=34A029590
- For n>0, a(n) is the least quasi-Carmichael number to base n; a(0) = least composite squarefree integer.at n=31A029590