521287 has 4 divisors (see below), whose sum is σ = 561400. Its totient is φ = 481176.

The previous prime is 521281. The next prime is 521299. The reversal of 521287 is 782125.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521287 is a prime.

It is a Duffinian number.

521287 is a modest number, since divided by 1287 gives 52 as remainder.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (521281) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20037 + ... + 20062.

It is an arithmetic number, because the mean of its divisors is an integer number (140350).

2⁵²¹²⁸⁷ is an apocalyptic number.

521287 is a deficient number, since it is larger than the sum of its proper divisors (40113).

521287 is a wasteful number, since it uses less digits than its factorization.

521287 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40112.

The product of its digits is 1120, while the sum is 25.

The square root of 521287 is about 722.0020775593. The cubic root of 521287 is about 80.4808024898.

It can be divided in two parts, 521 and 287, that added together give a palindrome (808).

The spelling of 521287 in words is "five hundred twenty-one thousand, two hundred eighty-seven".