3209
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 3210
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 3208
- Möbius Function
- -1
- Radical
- 3209
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 74
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 454
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of points of norm <= n^2 in square lattice.at n=32A000328
- Where the prime race among 7k+1, ..., 7k+6 changes leader.at n=25A007354
- Primes of form n^2 + n + 17.at n=39A007635
- Numbers k such that the continued fraction for sqrt(k) has period 41.at n=3A020380
- Palindromic primes in base 15.at n=32A029982
- Primes of form x^2+38*y^2.at n=34A033226
- Primes of the form x^2+74*y^2.at n=22A033248
- Coordination sequence T1 for Zeolite Code STF.at n=38A038443
- Numbers k such that the string 0,9 occurs in the base 10 representation of k but not of k-1.at n=34A044341
- Numbers n such that string 0,9 occurs in the base 10 representation of n but not of n+1.at n=34A044722
- Numbers n such that string 2,0 occurs in the base 10 representation of n but not of n+1.at n=35A044733
- Primes with first digit 3.at n=42A045709
- p, p+8 and p+12 are primes.at n=30A046141
- Number of partitions of n with equal nonzero number of parts congruent to each of 0, 1, 2 and 4 (mod 5).at n=64A046784
- Primes expressible in two ways as the sum of an integer and its digit sum.at n=40A048528
- Primes followed by an [8,4,8]=[d,D-d,d] prime difference pattern of A001223.at n=3A052377
- Number of orbits of length n under the map whose periodic points are counted by A001643.at n=17A060168
- Primes p that have exactly two primitive roots that are not primitive roots mod p^2.at n=17A060518
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 100 ).at n=20A063373
- a(n) = a(n-1) + floor(a(n-2)/2) with a(0)=1, a(1)=2.at n=26A064324