257263387 has 2 divisors, whose sum is σ = 257263388. Its totient is φ = 257263386.

The previous prime is 257263373. The next prime is 257263393. The reversal of 257263387 is 783362752.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 257263387 - 2²³ = 248874779 is a prime.

It is not a weakly prime, because it can be changed into another prime (257243387) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128631693 + 128631694.

It is an arithmetic number, because the mean of its divisors is an integer number (128631694).

Almost surely, 2^257263387 is an apocalyptic number.

257263387 is a deficient number, since it is larger than the sum of its proper divisors (1).

257263387 is an equidigital number, since it uses as much as digits as its factorization.

257263387 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 257263387 is about 16039.4322530444. The cubic root of 257263387 is about 636.0032394057.

The spelling of 257263387 in words is "two hundred fifty-seven million, two hundred sixty-three thousand, three hundred eighty-seven".