521257 has 4 divisors (see below), whose sum is σ = 568656. Its totient is φ = 473860.

The previous prime is 521251. The next prime is 521267. The reversal of 521257 is 752125.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-521257 is a prime.

It is not an unprimeable number, because it can be changed into a prime (521251) 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 3 ways as a sum of consecutive naturals, for example, 23683 + ... + 23704.

It is an arithmetic number, because the mean of its divisors is an integer number (142164).

2⁵²¹²⁵⁷ is an apocalyptic number.

It is an amenable number.

521257 is a deficient number, since it is larger than the sum of its proper divisors (47399).

521257 is a wasteful number, since it uses less digits than its factorization.

521257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47398.

The product of its digits is 700, while the sum is 22.

The square root of 521257 is about 721.9813016969. The cubic root of 521257 is about 80.4792585736.

The spelling of 521257 in words is "five hundred twenty-one thousand, two hundred fifty-seven".