257965387 has 2 divisors, whose sum is σ = 257965388. Its totient is φ = 257965386.

The previous prime is 257965381. The next prime is 257965397. The reversal of 257965387 is 783569752.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257965387 is a prime.

It is a super-2 number, since 2×257965387² = 133092281780119538, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (257965381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128982693 + 128982694.

It is an arithmetic number, because the mean of its divisors is an integer number (128982694).

Almost surely, 2^257965387 is an apocalyptic number.

257965387 is a deficient number, since it is larger than the sum of its proper divisors (1).

257965387 is an equidigital number, since it uses as much as digits as its factorization.

257965387 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3175200, while the sum is 52.

The square root of 257965387 is about 16061.3009124417. The cubic root of 257965387 is about 636.5812058141.

The spelling of 257965387 in words is "two hundred fifty-seven million, nine hundred sixty-five thousand, three hundred eighty-seven".