257545649 has 2 divisors, whose sum is σ = 257545650. Its totient is φ = 257545648.

The previous prime is 257545633. The next prime is 257545661. The reversal of 257545649 is 946545752.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 190633249 + 66912400 = 13807^2 + 8180^2 .

It is a cyclic number.

It is not a de Polignac number, because 257545649 - 2⁴ = 257545633 is a prime.

It is a super-2 number, since 2×257545649² = 132659522637662402, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257545349) 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, 128772824 + 128772825.

It is an arithmetic number, because the mean of its divisors is an integer number (128772825).

Almost surely, 2^257545649 is an apocalyptic number.

It is an amenable number.

257545649 is a deficient number, since it is larger than the sum of its proper divisors (1).

257545649 is an equidigital number, since it uses as much as digits as its factorization.

257545649 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1512000, while the sum is 47.

The square root of 257545649 is about 16048.2288430842. The cubic root of 257545649 is about 636.2357558861.

The spelling of 257545649 in words is "two hundred fifty-seven million, five hundred forty-five thousand, six hundred forty-nine".