13577
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 13578
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 13576
- Möbius Function
- -1
- Radical
- 13577
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 89
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1606
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Define the generalized Pisot sequence T(a(0),a(1)) by: a(n+2) is the greatest integer such that a(n+2)/a(n+1) < a(n+1)/a(n). This is T(3,5).at n=27A018917
- Primes of the form k^2 + k + 5.at n=32A027755
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 21.at n=4A031609
- Number of nonisomorphic cyclic subgroups of the group S_n X S_n (where S_n is the symmetric group of degree n).at n=49A063183
- Smallest prime with concatenation of first n odd numbers as leading digits.at n=3A068837
- a(1) = 1, a(n) = smallest prime number not already used such that concatenation of a(k) and a(n) is composite for all k = 1 to n-1.at n=42A075612
- Smallest prime which begins with the concatenation of n successive odd numbers.at n=3A087333
- Primes congruent to 32 mod 43.at n=33A142281
- Primes congruent to 41 mod 47.at n=37A142392
- Primes congruent to 4 mod 49.at n=36A142417
- Primes congruent to 9 mod 53.at n=34A142539
- Primes congruent to 47 mod 55.at n=39A142634
- Primes congruent to 7 mod 59.at n=24A142734
- Primes congruent to 35 mod 61.at n=28A142833
- Primes p such that p^3 - 24 and p^3 + 24 are also primes.at n=23A153323
- a(n)= sum_{i=7..n+6} A000931(i).at n=28A167385
- Monotonic ordering of nonnegative differences 5^i-2^j, for 40>=i>=0, j>=0.at n=41A192115
- Primes remaining primes under map 3<=>5 (interchange of decimal digits 3 and 5).at n=16A198047
- Primes of the form 16n^2 + 121.at n=10A202083
- Number of HSI-algebras on n elements, up to isomorphism.at n=4A214396