Number of the day: 9487

Stefan Banach was born on this day 129 years ago.

Properties of the number 9487:

9487 is a cyclic number.
9487 = 53 × 179 is semiprime and squarefree.
9487 has 2 distinct prime factors, 4 divisors, 25 antidivisors and 9256 totatives.
9487 has a triangular digit sum 28 in base 10.
9487 has a triangular digit product 2016 in base 10.
Reversing the decimal digits of 9487 results in an emirpimes.
9487 = 4744² - 4743² = 116² - 63² is the difference of 2 nonnegative squares in 2 ways.
9487 is the sum of 2 positive triangular numbers.
9487 is the difference of 2 positive pentagonal numbers in 1 way.
9487 is not the sum of 3 positive squares.
9487² = 5012² + 8055² is the sum of 2 positive squares in 1 way.
9487² is the sum of 3 positive squares.
9487 is a proper divisor of 1789²⁶ - 1.
9487 = '94' + '87' is the concatenation of 2 semiprime numbers.
9487 is an emirpimes in (at least) the following bases: 3, 4, 5, 6, 7, 9, 10, 11, 15, 18, 20, 21, 23, 25, 27, 31, 34, 36, 39, 42, 43, 50, 51, 55, 56, 59, 61, 65, 67, 68, 70, 71, 73, 75, 76, 79, 88, 89, 91, 95, 96, 97, 98, 99, and 100.
9487 is palindromic in (at least) base 93.
9487 in base 3 = 111000101 and consists of only the digits '0' and '1'.
9487 in base 43 = 55R and consists of only the digits '5' and 'R'.

The number 9487 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequences (among others):

Sequence numbers and descriptions below are taken from OEIS.
A011942: [ n(n-1)(n-2)(n-3)/32 ].
A020419: Numbers n such that continued fraction for sqrt(n) has period 80.
A022767: Ordered sequence of distinct terms of the form floor(Pi^i * floor(Pi^j)), i, j >= 0.
A031799: Period of continued fraction for sqrt(n) contains exactly 31 ones.
A035076: a(n) is root of square starting with digit 9: first term of runs.
A041540: Numerators of continued fraction convergents to sqrt(287).
A081490: Leading term of n-th row of A081491.
A194268: 8*n^2 + 7*n + 1.
A240733: Floor(6^n/(2+2*cos(Pi/9))^n).
A336561: Numbers k at which point A336459(k) appears multiplicative, but A051027(k) does not.