257891347 has 12 divisors (see below), whose sum is σ = 299674128. Its totient is φ = 217404000.

The previous prime is 257891317. The next prime is 257891357. The reversal of 257891347 is 743198752.

It is not a de Polignac number, because 257891347 - 2⁷ = 257891219 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 257891297 and 257891306.

It is not an unprimeable number, because it can be changed into a prime (257891317) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 21097 + ... + 30997.

It is an arithmetic number, because the mean of its divisors is an integer number (24972844).

Almost surely, 2^257891347 is an apocalyptic number.

257891347 is a deficient number, since it is larger than the sum of its proper divisors (41782781).

257891347 is an frugal number, since it uses more digits than its factorization.

257891347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10030 (or 9969 counting only the distinct ones).

The product of its digits is 423360, while the sum is 46.

The square root of 257891347 is about 16058.9958278841. The cubic root of 257891347 is about 636.5202971485.

The spelling of 257891347 in words is "two hundred fifty-seven million, eight hundred ninety-one thousand, three hundred forty-seven".