3791
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 4032
- Proper Divisor Sum (Aliquot Sum)
- 241
- 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
- 3552
- Möbius Function
- 1
- Radical
- 3791
- 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
- 175
- 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
- Number of symmetric plane partitions of n.at n=30A005987
- Oscillates under partition transform.at n=41A007210
- Coordination sequence T2 for Zeolite Code PAU.at n=45A008220
- If a, b in sequence, so is ab+7.at n=33A009312
- Coordination sequence T1 for Zeolite Code RTE.at n=42A009890
- Coordination sequence T2 for Zeolite Code RTE.at n=42A009891
- Number of binary sequences of length n with an even number of ones, at least two of the ones being contiguous.at n=12A027711
- 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 61.at n=5A031559
- a(1)=1, a(n) = smallest odd number such that all sums of pairs of (not necessarily distinct) terms in the sequence are distinct.at n=34A034757
- Coordination sequence T3 for Zeolite Code STF.at n=41A038442
- a(n)=(s(n)+4)/9, where s(n)=n-th base 9 palindrome that starts with 5.at n=36A043076
- Numbers m such that string 9,1 occurs in the base 10 representation of m but not of m+1.at n=40A044804
- Numbers whose base-4 representation contains exactly one 0 and four 3's.at n=27A045070
- Numbers whose base-4 representation contains no 1's and exactly four 3's.at n=30A045113
- Numbers whose base-4 representation contains exactly one 2 and four 3's.at n=30A045142
- Numbers n such that phi(phi(n)) = phi(sigma(n)) where phi is Euler's totient and sigma is the multiplicative sum-of-divisors function.at n=37A065555
- Expansion of (1-x)/(1-x-x^2+2*x^3).at n=36A078011
- a(n) = p^n + q^n, p = (1 + sqrt(21))/2, q = (1 - sqrt(21))/2.at n=7A085487
- a(n)=A089551(n)/2.at n=35A089558
- Slowest increasing sequence where the first pair of digits sums to 10, the next pair also does and so on.at n=39A098791