7187
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 7188
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7186
- Möbius Function
- -1
- Radical
- 7187
- 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
- 31
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 918
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Where the prime race among 5k+1, ..., 5k+4 changes leader.at n=40A007353
- T(2n,n-4), T given by A026747.at n=4A026859
- Primes that are palindromic in base 6.at n=26A029974
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 83.at n=29A031581
- Number of partitions of n with equal nonzero number of parts congruent to each of 0, 1 and 2 (mod 5).at n=58A035582
- Base-6 palindromes that start with 5.at n=33A043014
- Primes with first digit 7.at n=35A045713
- Primes p such that pp'-2 is prime, where p' denotes the next prime after p.at n=41A048797
- Primes p from A031924 such that A052180(primepi(p)) = 7.at n=36A052231
- Number of polyominoes with n cells, symmetric about two orthogonal axes.at n=29A056877
- Discriminants of imaginary quadratic fields with class number 25 (negated).at n=9A056987
- Smallest prime p such that x = n is a solution mod p of x^3 = 2, or 0 if no such prime exists.at n=31A059940
- a(1)=1; a(n) is the smallest positive integer that cannot be obtained from the integers {0, 1, ..., n-1} using each number at most once and the operators +, -, *, /.at n=8A060315
- Primes starting and ending with 7.at n=9A062334
- a(n) = 1^n + 5^n + 9^n.at n=4A074519
- Primes which are the sum of three positive 4th powers.at n=14A085318
- Numbers n such that 2*p(n)+3, 2*p(n+1)+3, 2*p(n+2)+3 are consecutive primes, where p(i) denotes the i-th prime.at n=8A088066
- Zeros of the Mertens function that are also prime.at n=43A100669
- Primes p such that 2*p-27, 2*p+27, 2*p-33 and 2*p+33 are primes or -1 times primes.at n=14A103807
- Sum of the right diagonal in ordered 3 X 3 prime squares.at n=39A105091