257130649 has 4 divisors (see below), whose sum is σ = 264080164. Its totient is φ = 250181136.

The previous prime is 257130631. The next prime is 257130691. The reversal of 257130649 is 946031752.

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 226803600 + 30327049 = 15060^2 + 5507^2 .

It is a cyclic number.

It is not a de Polignac number, because 257130649 - 2⁷ = 257130521 is a prime.

It is a super-2 number, since 2×257130649² = 132232341310322402, which contains 22 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: 6949477 = 257130649 / (2 + 5 + 7 + 1 + 3 + 0 + 6 + 4 + 9).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257170649) 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, 3474702 + ... + 3474775.

It is an arithmetic number, because the mean of its divisors is an integer number (66020041).

Almost surely, 2^257130649 is an apocalyptic number.

It is an amenable number.

257130649 is a deficient number, since it is larger than the sum of its proper divisors (6949515).

257130649 is an equidigital number, since it uses as much as digits as its factorization.

257130649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6949514.

The product of its (nonzero) digits is 45360, while the sum is 37.

The square root of 257130649 is about 16035.2938544948. The cubic root of 257130649 is about 635.8938361950.

The spelling of 257130649 in words is "two hundred fifty-seven million, one hundred thirty thousand, six hundred forty-nine".