Number of the day: 169087

Jacques Salomon Hadamard was born on this day 155 years ago.

Julia Robinson was born on this day 101 years ago.

Properties of the number 169087:

169087 is a cyclic number.
169087 = 353 × 479 is semiprime and squarefree.
169087 has 2 distinct prime factors, 4 divisors, 37 antidivisors and 168256 totatives.
169087 has an emirp digit sum 31 in base 10.
Reversing the decimal digits of 169087 results in a prime.
169087 = 84544² - 84543² = 416² - 63² is the difference of 2 nonnegative squares in 2 ways.
169087 is the sum of 2 positive triangular numbers.
169087 is the difference of 2 positive pentagonal numbers in 1 way.
169087 is not the sum of 3 positive squares.
169087² = 107775² + 130288² is the sum of 2 positive squares in 1 way.
169087² is the sum of 3 positive squares.
169087 is a proper divisor of 311⁹⁵⁶ - 1.
169087 is an emirpimes in (at least) the following bases: 2, 4, 5, 8, 11, 14, 17, 20, 23, 25, 32, 33, 35, 44, 45, 47, 52, 57, 62, 67, 71, 73, 76, 77, 78, 80, 81, 82, 85, 88, 89, 93, 94, and 98.
169087 is palindromic in (at least) base 79.
169087 in base 38 = 333P and consists of only the digits '3' and 'P'.

The number 169087 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A248880: Number of tilings of an n X 1 rectangle by tiles of dimension 1 X 1 and 2 X 1 such that every tile shares an equal-length edge with a tile of the same size.