Number of the day: 90131

Properties of the number 90131:

90131 is a cyclic number.
90131 = 193 × 467 is semiprime and squarefree.
90131 has 2 distinct prime factors, 4 divisors, 7 antidivisors and 89472 totatives.
90131 has a semiprime digit sum 14 in base 10.
Reversing the decimal digits of 90131 results in a prime.
90131 = 45066² - 45065² = 330² - 137² is the difference of 2 nonnegative squares in 2 ways.
90131 is the difference of 2 positive pentagonal numbers in 1 way.
90131 = 9² + 55² + 295² is the sum of 3 positive squares.
90131² = 44365² + 78456² is the sum of 2 positive squares in 1 way.
90131² is the sum of 3 positive squares.
90131 is a proper divisor of 1867¹² - 1.
90131 is an emirpimes in (at least) the following bases: 2, 3, 4, 9, 13, 16, 23, 25, 29, 31, 32, 36, 39, 42, 43, 44, 51, 55, 59, 60, 62, 64, 65, 66, 67, 75, 77, 87, 91, 93, 97, and 98.
90131 is palindromic in (at least) base 82.

The number 90131 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A207059: Nonnegative values x of solutions (x, y) to the Diophantine equation x^2 + (x+289)^2 = y^2.
A307881: 2*a(n) is the least number where k sets a new record such that 2*a(n)-k and 2*a(n)+k are prime and at least one of 2*a(n)-j and 2*a(n)+j is composite for all 0<j<k.
A328466: Row 3 of A328464: a(n) = A276156(8n - 4) / 6.