257138267 has 4 divisors (see below), whose sum is σ = 270671880. Its totient is φ = 243604656.

The previous prime is 257138263. The next prime is 257138281. The reversal of 257138267 is 762831752.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 257138267 - 2² = 257138263 is a prime.

It is a super-2 number, since 2×257138267² = 132240176711526578, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257138263) 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, 6766778 + ... + 6766815.

It is an arithmetic number, because the mean of its divisors is an integer number (67667970).

Almost surely, 2^257138267 is an apocalyptic number.

257138267 is a deficient number, since it is larger than the sum of its proper divisors (13533613).

257138267 is a wasteful number, since it uses less digits than its factorization.

257138267 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13533612.

The product of its digits is 141120, while the sum is 41.

The square root of 257138267 is about 16035.5313912574. The cubic root of 257138267 is about 635.9001160005.

The spelling of 257138267 in words is "two hundred fifty-seven million, one hundred thirty-eight thousand, two hundred sixty-seven".