3900
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 12152
- Proper Divisor Sum (Aliquot Sum)
- 8252
- 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
- 960
- Möbius Function
- 0
- Radical
- 390
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- 144
- 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
- Smallest k such that the product of q/(q-1) over the primes from prime(n) to prime(n+k-1) is greater than 2.at n=41A001276
- G.f.: 2*(1-x^3)/((1-x)^5*(1+x)^2).at n=23A005996
- a(n) = floor(n*(n-1)*(n-2)/4).at n=26A011886
- a(n) is least k such that k and 7k are anagrams in base n (written in base 10).at n=32A023099
- Areas of right triangles with coprime integer sides.at n=25A024365
- Ordered areas of primitive Pythagorean triangles.at n=27A024406
- dot product (n,n-1,...2,1).(3,4,...,n,1,2).at n=23A026054
- Coordination sequence T2 for Zeolite Code CGS.at n=46A027366
- 5 times triangular numbers: a(n) = 5*n*(n+1)/2.at n=39A028895
- Numbers k such that 253*2^k+1 is prime.at n=30A032503
- Numbers in which all pairs of consecutive base-8 digits differ by 3.at n=44A033079
- McKay-Thompson series of class 13A for the Monster group with a(0) = -2.at n=11A034318
- McKay-Thompson series of class 13A for the Monster group with a(0) = 0.at n=11A034319
- Sums of 4 distinct powers of 5.at n=14A038476
- Numbers k such that the string 0,0 occurs in the base 10 representation of k but not of k-1.at n=38A044332
- Numbers whose base-4 representation contains exactly two 0's and four 3's.at n=6A045075
- A convolution triangle of numbers obtained from A025751.at n=25A049224
- Number of n-node planar graphs with minimum degree at least 3.at n=8A049371
- 12 times triangular numbers.at n=25A049598
- Least k for which the integers floor(2k/(m*(m+1))) for m=1,2,...,n are distinct.at n=28A054064