15913
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
- 15914
- 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
- 15912
- Möbius Function
- -1
- Radical
- 15913
- 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
- 102
- 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
- 1855
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Number of proper covers of an n-set.at n=3A007537
- Multiplicity of trivial character in V_n, where V = Sum V_n is the graded module for the Monster simple group.at n=39A014810
- Numbers n such that n is a substring of its square (both n and n squared in base 4) (written in base 10).at n=28A018828
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 74 ones.at n=13A031842
- Third member of a sexy prime quadruple: value of p+12 such that p, p+6, p+12 and p+18 are all prime.at n=31A046123
- Primes p from A031924 such that A052180(primepi(p)) = 11.at n=33A052232
- Least prime in A031924 (lesser of 6-twins) such that the distance to the next 6-twin is 2*n.at n=41A052352
- Third term of balanced prime quartets: p(m-1)-p(m-2) = p(m)-p(m-1) = p(m+1)-p(m).at n=11A054802
- Primes p such that x^18 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=29A059664
- Primes p such that x^54 = 2 has no solution mod p, but x^6 = 2 has a solution mod p.at n=31A059665
- Numerators of continued fraction convergents to (sqrt(37)-4)/3.at n=13A082962
- Primes in A003154.at n=28A083577
- Smallest prime whose digits can be partitioned into n successive terms of an A.P. with common difference n, or 0 if no such number exists.at n=3A088253
- Least prime of Erdos-Selfridge class n+ in A129470.at n=2A129469
- Primes p of Erdos-Selfridge class 5+ with largest prime factor of p+1 not of class 4+.at n=0A129473
- Mother primes of order 8.at n=28A136067
- Primes congruent to 13 mod 53.at n=36A142543
- Primes congruent to 42 mod 59.at n=35A142769
- Primes congruent to 53 mod 61.at n=30A142851
- Primes p = prime(k) of form 13//r, s//13 or t//13//u and sod(p) = sod(k).at n=20A169645