3988
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 6986
- Proper Divisor Sum (Aliquot Sum)
- 2998
- 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
- 1992
- Möbius Function
- 0
- Radical
- 1994
- Omega Function (Ω)
- 3
- 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
- 51
- 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
- Numbers k such that k divides the (left) concatenation of all numbers <= k written in base 15 (most significant digit on right and removing all least significant zeros before concatenation).at n=10A029532
- Positive numbers having the same set of digits in base 7 and base 9.at n=19A037439
- Coordination sequence Z12 for Zeolite Code STT.at n=42A038416
- Discriminants of imaginary quadratic fields with class number 14 (negated).at n=41A046011
- Numbers k such that k and k-1 both have 6 divisors.at n=40A049104
- Starting positions of strings of 2 2's in the decimal expansion of Pi.at n=38A050215
- a(n) = a(n-1) + a(n - 1 minus the number of terms of a(k) == (mod 4) so far).at n=26A060731
- Sum of digits = 7 times number of digits.at n=42A061424
- Number of graphical partitions of simple Eulerian graphs (partitions given by the degrees of vertices of simple (no loops or multiple edges) graphs having only vertices of even degrees) having n edges.at n=39A069831
- a(n) = smallest multiple of 4 with sum of digits = n.at n=27A077489
- Square array of Pell related numbers, read by antidiagonals.at n=50A086350
- Smallest positive number that requires n iterations of f(k) to reach a single digit, where f(k) is the product of the two numbers formed from the alternating digits of k.at n=11A087473
- a(n) = the next n digits of phi, the golden ratio.at n=3A093473
- Number of one-element transitions from the partitions of n to the partitions of n+1 for labeled parts.at n=19A093694
- Nonprime terms of A115558.at n=42A115559
- Number of sums payable using exactly n banknotes of denominations 1, 5, 10, 20, 50, 100 (change allowable).at n=42A135526
- Expansion of (1-3*x)/(1-8*x+14*x^2).at n=5A161731
- Positive integers n such that the sum S of 1 and first n^2-1 odd primes is divisible by n and S/n == n (mod 2).at n=13A173079
- a(n) = 2^n - n*(n-3).at n=12A176777
- a(n) = 4*(10^n-3).at n=2A177108