257138268 has 12 divisors (see below), whose sum is σ = 599989320. Its totient is φ = 85712752.

The previous prime is 257138263. The next prime is 257138281. The reversal of 257138268 is 862831752.

It is a tau number, because it is divible by the number of its divisors (12).

It is a super-2 number, since 2×257138268² = 132240177740079648, which contains 22 as substring.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257138263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10714083 + ... + 10714106.

It is an arithmetic number, because the mean of its divisors is an integer number (49999110).

Almost surely, 2^257138268 is an apocalyptic number.

It is an amenable number.

257138268 is an abundant number, since it is smaller than the sum of its proper divisors (342851052).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257138268 is a wasteful number, since it uses less digits than its factorization.

257138268 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21428196 (or 21428194 counting only the distinct ones).

The product of its digits is 161280, while the sum is 42.

The square root of 257138268 is about 16035.5314224381. The cubic root of 257138268 is about 635.9001168248.

The spelling of 257138268 in words is "two hundred fifty-seven million, one hundred thirty-eight thousand, two hundred sixty-eight".