257027991 has 16 divisors (see below), whose sum is σ = 393536640. Its totient is φ = 147575520.

The previous prime is 257027987. The next prime is 257028019. The reversal of 257027991 is 199720752.

It is not a de Polignac number, because 257027991 - 2² = 257027987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257027941) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 204340 + ... + 205593.

It is an arithmetic number, because the mean of its divisors is an integer number (24596040).

Almost surely, 2^257027991 is an apocalyptic number.

257027991 is a deficient number, since it is larger than the sum of its proper divisors (136508649).

257027991 is a wasteful number, since it uses less digits than its factorization.

257027991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 409966.

The product of its (nonzero) digits is 79380, while the sum is 42.

The square root of 257027991 is about 16032.0925334156. The cubic root of 257027991 is about 635.8091992227.

The spelling of 257027991 in words is "two hundred fifty-seven million, twenty-seven thousand, nine hundred ninety-one".