13591
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 13592
- 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
- 13590
- Möbius Function
- -1
- Radical
- 13591
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 37
- 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
- 1607
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Let c(k) denote the k-th composite number and p(k) the k-th prime number; then a(n) = Sum_{i=n*(n-1)/2+1 .. n*(n+1)/2} c(i) - Sum_{i=1..n} p(i).at n=28A024850
- Palindromic primes in base 4.at n=31A029972
- a(1) = 1, a(n+1) = Sum_{k = 1..n} p(k)*a(n+1-k), where p(k) is the k-th prime.at n=8A030017
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 96 ones.at n=2A031864
- Primes p whose reciprocal has period (p-1)/10.at n=21A056215
- Primes p such that x^18 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=28A059664
- Primes p such that x^54 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=30A059665
- Primes p such that x^36 = 2 has no solution mod p, but x^12 = 2 has a solution mod p.at n=21A059668
- Sums of groups in A075635.at n=27A075636
- Convolution of sequence of primes with sequence sigma(n).at n=24A086718
- Number of partitions of n having exactly one part with multiplicity 3.at n=41A118808
- Primes for which the weight as defined in A117078 is 11 and the gap as defined in A001223 is 6.at n=26A119597
- Primes p such that p+1, p+2 and p+3 have equal number of divisors.at n=16A119711
- Mountain primes.at n=37A134951
- Primes congruent to 12 mod 37.at n=42A142121
- Primes congruent to 20 mod 41.at n=40A142217
- Primes congruent to 3 mod 43.at n=39A142252
- Primes congruent to 8 mod 47.at n=34A142359
- Primes congruent to 18 mod 49.at n=34A142429
- Primes congruent to 23 mod 53.at n=29A142553