520408657 has 4 divisors (see below), whose sum is σ = 520657060. Its totient is φ = 520160256.

The previous prime is 520408639. The next prime is 520408667. The reversal of 520408657 is 756804025.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 200392336 + 320016321 = 14156^2 + 17889^2 .

It is a cyclic number.

It is not a de Polignac number, because 520408657 - 2²⁷ = 386190929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (520408667) 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, 121032 + ... + 125257.

It is an arithmetic number, because the mean of its divisors is an integer number (130164265).

Almost surely, 2^520408657 is an apocalyptic number.

It is an amenable number.

520408657 is a deficient number, since it is larger than the sum of its proper divisors (248403).

520408657 is a wasteful number, since it uses less digits than its factorization.

520408657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 248402.

The product of its (nonzero) digits is 67200, while the sum is 37.

The square root of 520408657 is about 22812.4671397024. The cubic root of 520408657 is about 804.3557501138.

The spelling of 520408657 in words is "five hundred twenty million, four hundred eight thousand, six hundred fifty-seven".