15761
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
- 2
- Divisor Sum
- 15762
- 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
- 15760
- Möbius Function
- -1
- Radical
- 15761
- 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
- 146
- 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
- 1838
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Smallest prime containing n-th square as substring.at n=24A029948
- Smallest prime with "n^2" as central digit(s).at n=24A038370
- Numbers whose base-5 representation contains exactly three 0's and three 1's.at n=22A045172
- Primes p from A031924 such that A052180(primepi(p)) = 11.at n=32A052232
- Smallest prime containing the n-th square in decimal notation.at n=23A065144
- Final terms of rows of A077321.at n=39A077323
- a(n) = Sum_{i=1..n} C(i+6,7)^2.at n=3A086029
- a(n) = 10*n^2 - 6*n + 1.at n=39A087348
- Numbers k such that 2^k - 3*k is prime.at n=11A094963
- Primes in A103373.at n=18A103383
- Primes p equal to the sum of two successive sexy primes + 1 such that p + 6 is also prime.at n=27A104043
- Number triangle of sums of squared binomial coefficients.at n=62A110197
- Numbers k such that the k-th triangular number contains only digits {1,2,4}.at n=8A119100
- Primes for which the weight as defined in A117078 is 23.at n=37A119504
- Kekulé numbers for certain benzenoids (see the Cyvin-Gutman book for details).at n=8A123351
- Primes p of Erdos-Selfridge class 4+ with largest prime factor of p+1 not of class 3+.at n=10A129472
- Primes in A132286.at n=38A132287
- Primes of the form 210n+11.at n=36A140840
- Primes congruent to 16 mod 47.at n=39A142367
- Primes congruent to 20 mod 53.at n=31A142550