15773
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
- 15774
- 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
- 15772
- Möbius Function
- -1
- Radical
- 15773
- 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
- 177
- 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
- yes
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1840
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- n*10^2-1, n*10^2-3, n*10^2-7 and n*10^2-9 are all prime.at n=23A064976
- a(n) = numerator of Sum_{i=1..n} +-1/n, where the sign is -1 iff n is prime.at n=11A114998
- Smaller of two consecutive Sophie Germain primes with the same digital sum.at n=38A118506
- Larger of two consecutive Sophie Germain primes with the same digital sum.at n=37A118507
- Primes of the form 210k + 23.at n=37A140844
- Primes congruent to 28 mod 47.at n=38A142379
- Primes congruent to 32 mod 53.at n=34A142562
- Primes congruent to 20 mod 59.at n=31A142747
- Primes congruent to 35 mod 61.at n=31A142833
- Primes of the form : 2*p+1=p1(prime), 2*p1+3=p2(prime), 2*p2+5=p3(prime).at n=29A143912
- Primes p such that continued fraction of (1 + sqrt(p))/2 has period 7: primes in A146332.at n=27A146352
- Hypotenuses c of primitive Pythagorean Triples (a,b,c) such that 2*a+1, 2*b+1 and 2*c+1 are primes.at n=36A165238
- Numbers k such that A003418(k-1) = lcm(1,2,...,k-1) is congruent to 1 modulo k.at n=4A178629
- Primes p such that 100p-1, 100p-3, 100p-7, and 100p-9 are all prime.at n=4A243409
- Primes congruent to 11 mod 111.at n=26A252893
- Number of connected (6,2)-chordal bipartite graphs on n nodes.at n=11A280764
- Primes p of the form 8*k + 5 such that every odd prime divisor of p-1 has the form 8*t + 7.at n=32A306932
- SanD-50 primes: primes p such that p+d is also prime and sum of digits A007953(p(p+d)) = d, with d = 50.at n=37A307473
- Numbers that cannot be written as a difference of 11-smooth numbers.at n=24A326319
- a(n) is the least prime > a(n-2) such that a(n-1)+a(n) is a square.at n=23A359582