Number of the day: 71553

Richard Dedekind was born on this day 189 years ago.

Properties of the number 71553:

71553 = 3 × 17 × 23 × 61 is the 64465^th composite number and is squarefree.
71553 has 4 distinct prime factors, 16 divisors, 17 antidivisors and 42240 totatives.
71553 has a semiprime digit sum 21 in base 10.
71553 has a Fibonacci digit sum 21 in base 10.
71553 has a triangular digit sum 21 in base 10.
Reversing the decimal digits of 71553 results in a semiprime.
71553 = 35777² - 35776² = 11927² - 11924² = 2113² - 2096² = 1567² - 1544² = 727² - 676² = 617² - 556² = 553² - 484² = 287² - 104² is the difference of 2 nonnegative squares in 8 ways.
71553 is the sum of 2 positive triangular numbers.
71553 is the difference of 2 positive pentagonal numbers in 4 ways.
71553 = 11² + 26² + 266² is the sum of 3 positive squares.
71553² = 33672² + 63135² = 21735² + 68172² = 44505² + 56028² = 12903² + 70380² is the sum of 2 positive squares in 4 ways.
71553² is the sum of 3 positive squares.
71553 is a proper divisor of 599⁴ - 1.
71553 = '7' + '1553' is the concatenation of 2 prime numbers.
71553 is palindromic in (at least) the following bases: 73, and 88.
71553 in base 6 = 1311133 and consists of only the digits '1' and '3'.
71553 in base 53 = PP3 and consists of only the digits '3' and 'P'.

The number 71553 belongs to the following On-Line Encyclopedia of Integer Sequences (OEIS) sequence (among others):

Sequence number and description below are taken from OEIS.
A305262: a(n) = 140*2^n - 127.