257632387 has 2 divisors, whose sum is σ = 257632388. Its totient is φ = 257632386.

The previous prime is 257632363. The next prime is 257632391. The reversal of 257632387 is 783236752.

257632387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257632387 - 2²⁷ = 123414659 is a prime.

It is not a weakly prime, because it can be changed into another prime (257632337) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128816193 + 128816194.

It is an arithmetic number, because the mean of its divisors is an integer number (128816194).

Almost surely, 2^257632387 is an apocalyptic number.

257632387 is a deficient number, since it is larger than the sum of its proper divisors (1).

257632387 is an equidigital number, since it uses as much as digits as its factorization.

257632387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 423360, while the sum is 43.

The square root of 257632387 is about 16050.9310321863. The cubic root of 257632387 is about 636.3071731579.

The spelling of 257632387 in words is "two hundred fifty-seven million, six hundred thirty-two thousand, three hundred eighty-seven".