Number of the day: 6143

Properties of the number 6143:

6143 is a cyclic number.
6143 is the 801^th prime.
6143 has 33 antidivisors and 6142 totatives.
6143 has a semiprime digit sum 14 in base 10.
6143 has an oblong digit product 72 in base 10.
6143 = 3072² - 3071² is the difference of 2 nonnegative squares in 1 way.
6143 is the difference of 2 positive pentagonal numbers in 1 way.
6143 is not the sum of 3 positive squares.
6143² is the sum of 3 positive squares.
6143 is a proper divisor of 409³⁷ - 1.
6143 = '61' + '43' is the concatenation of 2 prime numbers.
6143 = '6' + '143' is the concatenation of 2 semiprime numbers.
6143 is an emirp in (at least) the following bases: 7, 13, 15, 16, 17, 26, 37, 44, 49, 57, 58, 65, 66, 69, 76, 79, 83, 84, 85, 86, 88, 91, 94, 97, and 99.
6143 is palindromic in (at least) the following bases: 33, 74, -69, and -83.
6143 in base 4 = 1133333 and consists of only the digits '1' and '3'.
6143 in base 32 = 5vv and consists of only the digits '5' and 'v'.
6143 in base 33 = 5l5 and consists of only the digits '5' and 'l'.

The number 6143 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A005105: Class 1+ primes: primes of the form 2^i*3^j - 1 with i, j >= 0.
A045712: Primes with first digit 6.
A052955: a(2n) = 2*2^n - 1, a(2n+1) = 3*2^n - 1.
A055010: a(0) = 0; for n > 0, a(n) = 3*2^(n-1) - 1.
A061712: Smallest prime with Hamming weight n (i.e., with exactly n 1's when written in binary).
A083329: a(0) = 1; for n > 0, a(n) = 3*2^(n-1) - 1.
A113156: Primes such that the sum of the predecessor and successor primes is divisible by 37.
A127581: Smallest prime of the form k*2^n - 1, for k >= 2.
A141908: Primes congruent to 2 mod 23.
A153893: a(n) = 3*2^n - 1.