13011
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17352
- Proper Divisor Sum (Aliquot Sum)
- 4341
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8672
- Möbius Function
- 1
- Radical
- 13011
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 138
- 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
- a(n) = 10000*log_10(n) rounded up.at n=19A004230
- a(n) = floor(n*(n-1)*(n-2)/7).at n=46A011889
- Number of partitions satisfying (cn(0,5) = 0 and cn(2,5) = cn(3,5)).at n=52A036815
- G.f.: (21+98*x+91*x^2+21*x^3+x^4)/(1-x)^5.at n=5A160768
- Least binary palindrome (cf. A006995) with n binary digits such that the number of contiguous palindromic bit patterns is minimal.at n=13A217097
- Binary palindromes (cf. A006995) such that the number of contiguous palindromic bit patterns is minimal (for a given number of places).at n=32A217099
- T(n,k)=Number of (n+1)X(k+1) 0..3 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=45A231463
- Number of (1+1) X (n+1) 0..3 arrays with no element unequal to a strict majority of its horizontal, diagonal and antidiagonal neighbors, with values 0..3 introduced in row major order.at n=9A231464
- Number of nX2 0..3 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..3 introduced in row major order.at n=4A241323
- T(n,k)=Number of nXk 0..3 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..3 introduced in row major order.at n=19A241328
- Number of 5Xn 0..3 arrays with no element equal to fewer vertical neighbors than horizontal neighbors, with new values 0..3 introduced in row major order.at n=1A241332
- Partial sums of A255744.at n=21A255765
- Number of partitions of n into two sorts of parts having exactly 2 parts of the second sort.at n=17A258472
- Indices of primes followed by a gap (distance to next larger prime) of 44.at n=10A320720
- Semiprimes A001358(k) = p*q such that p*q+p+q and r*s+r+s are consecutive primes, where A001358(k+1)=r*s.at n=6A330478
- Numbers that are both binary palindromes and binary Smith numbers.at n=32A334530
- Numbers k such that k, k+1, k+2, k+3 have 2, 3, 4, 5 prime factors respectively, counted with multiplicity.at n=14A363391