13754
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 23226
- Proper Divisor Sum (Aliquot Sum)
- 9472
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6072
- Möbius Function
- 0
- Radical
- 598
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 151
- 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
- a(n) = (2*n-1)*(n^2 -n +6)/6.at n=34A049480
- Number of 2 X 2 singular integer matrices with elements from {0,...,n}.at n=41A059306
- Molien series for complete weight enumerators of self-dual codes over Z/8Z.at n=14A092544
- a(0)=0; then a(4*k+1)=a(4*k)+(4*k+1)^2, a(4*k+2)=a(4*k+1)+(4*k+3)^2, a(4*k+3)=a(4*k+2)+(4*k+2)^2, a(4*k+4)=a(4*k+3)+(4*k+4)^2.at n=34A115391
- Sums of two successive primes s such that s+-3 are primes.at n=27A179485
- Number of lower triangles of an n X n 0..7 array with each element differing from all of its horizontal and vertical neighbors by one.at n=4A194997
- Number of lower triangles of a 5 X 5 0..n array with each element differing from all of its horizontal and vertical neighbors by one.at n=6A195001
- Number of (n+1)X(n+1) -5..5 symmetric matrices with every 2X2 subblock having sum zero and three or four distinct values.at n=4A211334
- a(n) = 26*n^2.at n=23A244633
- Numbers k, the smallest of at least 4 consecutive numbers x, for which phi(x) <= phi(x+1).at n=44A295865
- Numbers k such that phi(k) < phi(k+1) < phi(k+2) < phi(k+3) where phi is the Euler totient function (A000010).at n=31A327880
- a(n) = Sum_{k=0..n} 2^k * k^(n-k).at n=8A351279
- Square array T(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where T(n,k) is Sum_{j=0..n} k^j * j^(n-j).at n=63A351339
- a(n) = T(n, 3), where T(n, k) = Sum_{i=0..n} i^k * binomial(n, i) * (1/2)^(n-k).at n=23A366151