3909
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5216
- Proper Divisor Sum (Aliquot Sum)
- 1307
- 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
- 2604
- Möbius Function
- 1
- Radical
- 3909
- 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
- 100
- 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
- Expansion of g.f. 1/((1-x)*(1-2*x)*(1-7*x)).at n=4A016201
- Numbers k such that the continued fraction for sqrt(k) has period 74.at n=6A020413
- 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 40.at n=28A031538
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 36 ones.at n=10A031804
- Multiplicity of highest weight (or singular) vectors associated with character chi_50 of Monster module.at n=39A034438
- Decimal part of a(n)^(1/n) starts with a pandigital anagram (digits 0 through 9 in some order).at n=29A035304
- Number of partitions of n such that cn(0,5) = cn(1,5) <= cn(2,5) = cn(4,5) < cn(3,5).at n=64A036863
- Least k such that A038025(k)=n-th composite number or 0 if none.at n=17A038027
- Numbers k such that the string 0,9 occurs in the base 10 representation of k but not of k-1.at n=41A044341
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 22.at n=21A051963
- Numbers k such that k * (1+i)^k + 1 is a Gaussian prime.at n=22A058770
- Numbers n such that n^2*2^n - n*2^((n + 1)/2) + 1 is prime.at n=8A058778
- n * (1+i)^n + i is a Gaussian prime.at n=17A058782
- Numbers k such that the binary expansion of 3^k has the same number of 0's and 1's.at n=36A078839
- Main diagonal of array in A082191.at n=40A082194
- Row sums of triangle A084408.at n=20A084411
- a(n) = 2*n^2 + n - 7.at n=44A100041
- Structured small rhombicubeoctahedral numbers.at n=8A100149
- Numerators of row sums of array of rationals A038566(n)/A020653(n), n>=2.at n=7A111992
- Numbers k such that k^3 contains a pandigital substring.at n=1A115933