3031
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 7
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3472
- Proper Divisor Sum (Aliquot Sum)
- 441
- 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
- 2592
- Möbius Function
- 1
- Radical
- 3031
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 141
- 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
- Number of partitions of n if there are two kinds of 1, two kinds of 2 and two kinds of 3.at n=16A000098
- a(n) = n concatenated with n + 1.at n=29A001704
- Number of labeled connected bipartite graphs on n nodes.at n=5A001832
- Number of 5th-order maximal independent sets in path graph.at n=45A007380
- a(n) = n*(31*n-1)/2.at n=14A022288
- n written in fractional base 6/3.at n=31A024636
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n-k+1), where k = floor( n/2 ), s = natural numbers >= 3.at n=27A024875
- Number of n-polyplets (polyominoes connected at edges or corners); may contain holes.at n=6A030222
- Pair up the numbers.at n=15A030656
- 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 55.at n=1A031553
- Lucky numbers that are decimal concatenations of n with n + 1.at n=3A032651
- Coordination sequence T1 for Zeolite Code SBT.at n=44A033612
- Concatenation of two or more consecutive positive integers.at n=38A035333
- (s(n)+7)/10, where s(n)=n-th base 10 palindrome that starts with 3.at n=25A043082
- Numbers n such that string 3,1 occurs in the base 10 representation of n but not of n-1.at n=33A044363
- Numbers n such that string 3,1 occurs in the base 10 representation of n but not of n+1.at n=33A044744
- Numbers whose base-5 representation contains exactly three 1's and two 4's.at n=9A045261
- Number of partitions of n with equal number of even and odd parts.at n=41A045931
- Concatenate "n" and "nextprime(n)".at n=29A049852
- Trajectory of 23 under map that sends x to 3x - sigma(x), where sigma(x) is the sum of the divisors of x.at n=9A058545