13540
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 28476
- Proper Divisor Sum (Aliquot Sum)
- 14936
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5408
- Möbius Function
- 0
- Radical
- 6770
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 3
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
- 182
- 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
- Numerators of continued fraction convergents to sqrt(773).at n=6A042490
- a(n) is the number of integers whose sum of divisors is 6^n.at n=19A048253
- a(n) = a(1) + a(2) + ... + a(n-1) - a(m) for n >= 4, where m = n - 1 - 2^p and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = 1, a(2) = 3, and a(3) = 1.at n=15A049918
- a(n) = floor(7^n/4^n).at n=17A094980
- Times in hours, minutes and seconds (to the nearest second) at which the hour and minute hands of an analog clock, if interchanged, continue to indicate some other albeit accurate times, over a complete 12-hour sweep for the slower hand. Leading zeros omitted.at n=19A121577
- a(n) = 7*a(n-1)-n for n> 0, a(0)=1.at n=5A122471
- Number of trees that have a maximum 'n'.at n=25A168542
- Number of line segments connecting exactly 7 points in an n X n grid of points.at n=34A177723
- Number of arrays of 4 integers in -n..n with sum zero and adjacent elements differing in absolute value.at n=13A202964
- Number of partitions of n containing m(5) as a part, where m denotes multiplicity.at n=41A240490
- Number of length n+3 0..4 arrays with no four elements in a row with pattern abba (possibly a=b) and new values 0..4 introduced in 0..4 order.at n=5A243029
- T(n,k)=Number of length n+3 0..k arrays with no four elements in a row with pattern abba (possibly a=b) and new values 0..k introduced in 0..k order.at n=41A243033
- a(n) = n*(15*n^2 - 15*n + 4).at n=10A272134
- Numbers n such that Bernoulli number B_{n} has denominator 330.at n=37A272183
- Partial sums of the Dedekind psi_2(k) function, for 1 <= k <= n.at n=32A321973
- a(0) = ... = a(4) = 1; a(n) = Sum_{k=1..n-5} a(k) * a(n-k-5).at n=33A346049
- Rademacher's partition formula extended to half-integers. a(n) = round(sqrt(48) * (cosh(h(n)) - sinh(h(n))/h(n)) / (24*n + 11)) where h(n) = sqrt(24*n + 11)*(Pi/6).at n=34A376876
- Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where A(n,k) = Sum_{i=0..k*n} 2^i * Sum_{j=0..i} (-1)^j * binomial(i,j) * binomial(i-j,n)^k.at n=17A384362