257920331 has 2 divisors, whose sum is σ = 257920332. Its totient is φ = 257920330.

The previous prime is 257920297. The next prime is 257920357. The reversal of 257920331 is 133029752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257920331 - 2¹⁸ = 257658187 is a prime.

It is a super-2 number, since 2×257920331² = 133045794286299122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257920391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128960165 + 128960166.

It is an arithmetic number, because the mean of its divisors is an integer number (128960166).

Almost surely, 2^257920331 is an apocalyptic number.

257920331 is a deficient number, since it is larger than the sum of its proper divisors (1).

257920331 is an equidigital number, since it uses as much as digits as its factorization.

257920331 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 11340, while the sum is 32.

The square root of 257920331 is about 16059.8982250822. The cubic root of 257920331 is about 636.5441420912.

The spelling of 257920331 in words is "two hundred fifty-seven million, nine hundred twenty thousand, three hundred thirty-one".