257904512649 has 63 divisors (see below), whose sum is σ = 449978753757. Its totient is φ = 147319160184.

The previous prime is 257904512639. The next prime is 257904512687. The reversal of 257904512649 is 946215409752.

It is a happy number.

The square root of 257904512649 is 507843.

It is a perfect power (a square), and thus also a powerful number.

257904512649 is a `hidden beast` number, since 2 + 579 + 0 + 4 + 5 + 1 + 2 + 64 + 9 = 666.

It is a tau number, because it is divible by the number of its divisors (63).

It is not a de Polignac number, because 257904512649 - 2¹¹ = 257904510601 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 257904512595 and 257904512604.

It is not an unprimeable number, because it can be changed into a prime (257904512629) 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 in 62 ways as a sum of consecutive naturals, for example, 95980984 + ... + 95983670.

Almost surely, 2^257904512649 is an apocalyptic number.

257904512649 is the 507843-rd square number.

257904512649 is the 253922-nd centered octagonal number.

It is an amenable number.

257904512649 is a deficient number, since it is larger than the sum of its proper divisors (192074241108).

257904512649 is an frugal number, since it uses more digits than its factorization.

257904512649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5406 (or 2697 counting only the distinct ones).

The product of its (nonzero) digits is 5443200, while the sum is 54.

The spelling of 257904512649 in words is "two hundred fifty-seven billion, nine hundred four million, five hundred twelve thousand, six hundred forty-nine".