3924
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 10010
- Proper Divisor Sum (Aliquot Sum)
- 6086
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 1296
- Möbius Function
- 0
- Radical
- 654
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 25
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Coordination sequence T8 for Zeolite Code MFS.at n=39A008180
- Coordination sequence T6 for Zeolite Code MTW.at n=41A008201
- Coordination sequence T3 for Zeolite Code IFR.at n=44A024984
- Numbers k such that the string 2,4 occurs in the base 10 representation of k but not of k-1.at n=43A044356
- Twice second pentagonal numbers.at n=36A049451
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2^(p+1) + 2 - n and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 3, and a(3) = 1.at n=40A050057
- e-perfect numbers: numbers k such that the sum of the e-divisors (exponential divisors) of k equals 2*k.at n=36A054979
- Positive numbers whose product of digits is 12 times their sum.at n=32A062045
- Rounded volume of a regular dodecahedron with edge length n.at n=8A071401
- Numbers k such that phi(k) is a perfect biquadrate.at n=41A078164
- For each possible representation of n as n = 2*nb + 3*nu + K with nb, nu, K nonnegative integers, add numbers K, K+1, ..., 2*K except for 2*K-1 into a multiset. a(n) is the size of the resulting multiset minus the number of distinct numbers in it.at n=50A090666
- Numbers k such that 7^k - 2 is a prime.at n=20A090669
- Numbers k such that the k-th cyclotomic polynomial evaluated at 2 (=A019320(k)) is not coprime to k.at n=37A093106
- Number of simple graphs g on n nodes with |Aut(g)| = 12.at n=8A095853
- Number of distinct values of i*j + j*k + k*i with 1 <= i<j<k <= n.at n=44A100439
- In the interior of a regular 2n-gon with all diagonals drawn, the number of points where exactly three diagonals intersect.at n=16A101363
- Number of unrooted Eulerian n-edge maps in the plane (planar with a distinguished outside face).at n=7A103939
- Positive integers n such that n^10 + 1 is semiprime.at n=42A105078
- a(1) = 932; for n > 1, a(n) = a(n-1) + 1 + sum of distinct prime factors of a(n-1) that are < a(n-1).at n=11A105213
- Numbers that have exactly five prime factors counted with multiplicity (A014614) whose digit reversal is different and also has 5 prime factors (with multiplicity).at n=23A109025