13490
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 25920
- Proper Divisor Sum (Aliquot Sum)
- 12430
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5040
- Möbius Function
- 1
- Radical
- 13490
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- 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
- 76
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Sum of the first 2n+1 primes.at n=38A109723
- Pentagonal numbers (A000326) whose digit reversal is a prime.at n=15A115707
- Pentagonal numbers divisible by 5.at n=38A117793
- Numbers whose square is a permutational number A134640.at n=37A134742
- A051838 gives numbers m such that the sum of first m primes divides the product of the first m primes. This sequence gives corresponding values of the sum of first m primes.at n=19A140763
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, 0, 0), (0, -1, 0), (0, 1, 1), (1, 0, 1), (1, 1, -1)}.at n=7A150851
- Expansion of (x^2+1)/(x^4+2*x^3-2*x+1).at n=17A188802
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^3 >= x^3 + y^3.at n=36A211651
- Numbers in A007504 such that omega(a(n)) = Omega(a(n)) = 4.at n=2A264887
- Number of n X n 0..1 arrays with every element equal to 1, 2, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.at n=6A299608
- Number of nX7 0..1 arrays with every element equal to 1, 2, 4, 6, 7 or 8 king-move adjacent elements, with upper left element zero.at n=6A299611
- a(n) = (A001359(n+1)^2 - 1)/24, where A001359 = lesser of twin primes; or: pentagonal numbers (A000326) whose indices are twin ranks (A002822).at n=24A308344
- The number of even prime gaps g, satisfying g == 0 (mod 6), out of the first 2^n even prime gaps.at n=15A340948
- a(n) is the least m such that A341284(m) = 2*n*prime(m+1) - prime(m).at n=50A342027
- Positive integers in which the sum of the k-th powers of their digits is a prime number for k = 1, 2, 3, 4, 5, and 6 but not for k=7.at n=45A359449
- Pentagonal numbers which are the sum of the first k primes, for some k >= 0.at n=2A364691
- a(1) = 1. For n > 1; a(n) is equal to a(n-1) plus the decimal value of the concatenation of the first n-1 digits of the sequence.at n=5A375507
- a(n) = floor(n!*(e - 1/24)).at n=7A377013
- Pentagonal numbers which are products of four distinct primes.at n=12A381919
- Indices where the cumulative sum of sin(2k+1)^(2k+1) reaches a record high value.at n=32A387706