521557057 has 4 divisors (see below), whose sum is σ = 596065216. Its totient is φ = 447048900.

The previous prime is 521557027. The next prime is 521557061. The reversal of 521557057 is 750755125.

It is a happy number.

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 not a de Polignac number, because 521557057 - 2¹¹ = 521555009 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (521557027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 37254069 + ... + 37254082.

It is an arithmetic number, because the mean of its divisors is an integer number (149016304).

Almost surely, 2^521557057 is an apocalyptic number.

It is an amenable number.

521557057 is a deficient number, since it is larger than the sum of its proper divisors (74508159).

521557057 is an equidigital number, since it uses as much as digits as its factorization.

521557057 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74508158.

The product of its (nonzero) digits is 61250, while the sum is 37.

The square root of 521557057 is about 22837.6237161400. The cubic root of 521557057 is about 804.9469800349.

The spelling of 521557057 in words is "five hundred twenty-one million, five hundred fifty-seven thousand, fifty-seven".