520525657 has 4 divisors (see below), whose sum is σ = 534593956. Its totient is φ = 506457360.

The previous prime is 520525639. The next prime is 520525661. The reversal of 520525657 is 756525025.

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 198359056 + 322166601 = 14084^2 + 17949^2 .

It is a cyclic number.

It is not a de Polignac number, because 520525657 - 2¹⁹ = 520001369 is a prime.

It is a super-3 number, since 3×520525657³ (a number of 27 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37), and also a Moran number because the ratio is a prime number: 14068261 = 520525657 / (5 + 2 + 0 + 5 + 2 + 5 + 6 + 5 + 7).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (520525157) 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, 7034094 + ... + 7034167.

It is an arithmetic number, because the mean of its divisors is an integer number (133648489).

Almost surely, 2^520525657 is an apocalyptic number.

It is an amenable number.

520525657 is a deficient number, since it is larger than the sum of its proper divisors (14068299).

520525657 is a wasteful number, since it uses less digits than its factorization.

520525657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14068298.

The product of its (nonzero) digits is 105000, while the sum is 37.

The square root of 520525657 is about 22815.0313828406. The cubic root of 520525657 is about 804.4160249060.

The spelling of 520525657 in words is "five hundred twenty million, five hundred twenty-five thousand, six hundred fifty-seven".