257578457 has 2 divisors, whose sum is σ = 257578458. Its totient is φ = 257578456.

The previous prime is 257578429. The next prime is 257578469. The reversal of 257578457 is 754875752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 236821321 + 20757136 = 15389^2 + 4556^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257578457 is a prime.

It is not a weakly prime, because it can be changed into another prime (257578427) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128789228 + 128789229.

It is an arithmetic number, because the mean of its divisors is an integer number (128789229).

Almost surely, 2^257578457 is an apocalyptic number.

It is an amenable number.

257578457 is a deficient number, since it is larger than the sum of its proper divisors (1).

257578457 is an equidigital number, since it uses as much as digits as its factorization.

257578457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2744000, while the sum is 50.

The square root of 257578457 is about 16049.2509794071. The cubic root of 257578457 is about 636.2627708204.

The spelling of 257578457 in words is "two hundred fifty-seven million, five hundred seventy-eight thousand, four hundred fifty-seven".