257364391 has 2 divisors, whose sum is σ = 257364392. Its totient is φ = 257364390.

The previous prime is 257364389. The next prime is 257364407. The reversal of 257364391 is 193463752.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 257364391 - 2¹ = 257364389 is a prime.

Together with 257364389, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (257364311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128682195 + 128682196.

It is an arithmetic number, because the mean of its divisors is an integer number (128682196).

Almost surely, 2^257364391 is an apocalyptic number.

257364391 is a deficient number, since it is larger than the sum of its proper divisors (1).

257364391 is an equidigital number, since it uses as much as digits as its factorization.

257364391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 136080, while the sum is 40.

The square root of 257364391 is about 16042.5805592492. The cubic root of 257364391 is about 636.0864621123.

The spelling of 257364391 in words is "two hundred fifty-seven million, three hundred sixty-four thousand, three hundred ninety-one".