### Properties of the number 7127:

7127 and 7129 form a twin prime pair.7127 has 5 antidivisors and 7126 totatives.

7127 has an emirp digit sum 17 in base 10.

Reversing the decimal digits of 7127 results in a semiprime.

7127 = 3564

^{2}- 3563

^{2}is the difference of 2 nonnegative squares in 1 way.

7127 is the difference of 2 positive pentagonal numbers in 1 way.

7127 is not the sum of 3 positive squares.

7127

^{2}is the sum of 3 positive squares.

7127 is a divisor of 3

^{509}- 1.

7127 = '7' + '127' is the concatenation of 2 prime numbers.

7127 is an emirp in (at least) the following bases: 2, 6, 7, 11, 13, 18, 19, 20, 21, 25, 37, 39, 41, 43, 49, 53, 55, 60, 65, 76, 84, 85, 90, and 93.

7127 is palindromic in (at least) the following bases: 57, -52, and -75.

7127 in base 6 = 52555 and consists of only the digits '2' and '5'.

7127 in base 13 = 3323 and consists of only the digits '2' and '3'.

7127 in base 56 = 2FF and consists of only the digits '2' and 'F'.

7127 in base 57 = 2B2 and consists of only the digits '2' and 'B'.

7127 in base 59 = 22l and consists of only the digits '2' and 'l'.

### The number 7127 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.A000945: Euclid-Mullin sequence: a(1) = 2, a(n+1) is smallest prime factor of 1 + Product_{k=1..n} a(k).

A045713: Primes with first digit 7.

A050268: Primes of the form 36*n^2 - 810*n + 2753, listed in order of increasing parameter n >= 0.

A090287: Smallest prime obtained by sandwiching n between a number with identical digits, or 0 if no such prime exists. Primes of the form k n k where all the digits of k are identical.

A129658: Numerators of the convergents of the continued fraction for L(3, chi3), where L(s, chi3) is the Dirichlet L-function for the non-principal character modulo 3.

A134971: Canyon primes.

A136074: Father primes of order 5.

A174913: Lesser of twin primes p1 such that 2*p1+p2 is a prime number.

A204867: T(n,k)=Number of (n+2)X(k+2) 0..1 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly two different ways, and new values 0..1 introduced in row major order

A263358: Expansion of Product_{k>=1} 1/(1-x^(k+2))^k.

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