257906247 has 16 divisors (see below), whose sum is σ = 366048000. Its totient is φ = 161054784.

The previous prime is 257906239. The next prime is 257906333. The reversal of 257906247 is 742609752.

It is not a de Polignac number, because 257906247 - 2³ = 257906239 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 257906199 and 257906208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257906237) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20347 + ... + 30492.

It is an arithmetic number, because the mean of its divisors is an integer number (22878000).

Almost surely, 2^257906247 is an apocalyptic number.

257906247 is a deficient number, since it is larger than the sum of its proper divisors (108141753).

257906247 is a wasteful number, since it uses less digits than its factorization.

257906247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50950.

The product of its (nonzero) digits is 211680, while the sum is 42.

The square root of 257906247 is about 16059.4597356200. The cubic root of 257906247 is about 636.5325555019.

The spelling of 257906247 in words is "two hundred fifty-seven million, nine hundred six thousand, two hundred forty-seven".