257891481 has 27 divisors (see below), whose sum is σ = 383467357. Its totient is φ = 167013600.

The previous prime is 257891453. The next prime is 257891527. The reversal of 257891481 is 184198752.

The square root of 257891481 is 16059.

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

It can be written as a sum of positive squares in 4 ways, for example, as 136539225 + 121352256 = 11685^2 + 11016^2 .

It is not a de Polignac number, because 257891481 - 2¹¹ = 257889433 is a prime.

It is a super-2 number, since 2×257891481² = 133016031944746722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257811481) 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 26 ways as a sum of consecutive naturals, for example, 2553331 + ... + 2553431.

Almost surely, 2^257891481 is an apocalyptic number.

257891481 is the 16059-th square number.

257891481 is the 8030-th centered octagonal number.

It is an amenable number.

257891481 is a deficient number, since it is larger than the sum of its proper divisors (125575876).

257891481 is an equidigital number, since it uses as much as digits as its factorization.

257891481 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 314 (or 157 counting only the distinct ones).

The product of its digits is 161280, while the sum is 45.

The cubic root of 257891481 is about 636.5204073935.

The spelling of 257891481 in words is "two hundred fifty-seven million, eight hundred ninety-one thousand, four hundred eighty-one".