257108393 has 4 divisors (see below), whose sum is σ = 257141700. Its totient is φ = 257075088.

The previous prime is 257108359. The next prime is 257108407. The reversal of 257108393 is 393801752.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 18344089 + 238764304 = 4283^2 + 15452^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-257108393 is a prime.

It is a super-2 number, since 2×257108393² = 132209451502084898, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257105393) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1583 + ... + 22731.

It is an arithmetic number, because the mean of its divisors is an integer number (64285425).

Almost surely, 2^257108393 is an apocalyptic number.

It is an amenable number.

257108393 is a deficient number, since it is larger than the sum of its proper divisors (33307).

257108393 is a wasteful number, since it uses less digits than its factorization.

257108393 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 33306.

The product of its (nonzero) digits is 45360, while the sum is 38.

The square root of 257108393 is about 16034.5998702805. The cubic root of 257108393 is about 635.8754890219.

The spelling of 257108393 in words is "two hundred fifty-seven million, one hundred eight thousand, three hundred ninety-three".