521505 has 16 divisors (see below), whose sum is σ = 927360. Its totient is φ = 278064.

The previous prime is 521503. The next prime is 521519. The reversal of 521505 is 505125.

521505 is digitally balanced in base 7, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 521505 - 2¹ = 521503 is a prime.

It is an Ulam number.

521505 is strictly pandigital in base 7.

It is a Curzon number.

521505 is a lucky number.

It is a nialpdrome in base 9.

It is not an unprimeable number, because it can be changed into a prime (521503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1797 + ... + 2066.

It is an arithmetic number, because the mean of its divisors is an integer number (57960).

2⁵²¹⁵⁰⁵ is an apocalyptic number.

It is an amenable number.

521505 is a deficient number, since it is larger than the sum of its proper divisors (405855).

521505 is a wasteful number, since it uses less digits than its factorization.

521505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3877 (or 3871 counting only the distinct ones).

The product of its (nonzero) digits is 250, while the sum is 18.

The square root of 521505 is about 722.1530308737. The cubic root of 521505 is about 80.4920198357.

The spelling of 521505 in words is "five hundred twenty-one thousand, five hundred five".