257727138 has 8 divisors (see below), whose sum is σ = 515454288. Its totient is φ = 85909044.

The previous prime is 257727137. The next prime is 257727139. The reversal of 257727138 is 831727752.

It is an interprime number because it is at equal distance from previous prime (257727137) and next prime (257727139).

It is a sphenic number, since it is the product of 3 distinct primes.

257727138 is an admirable number.

It is a self number, because there is not a number n which added to its sum of digits gives 257727138.

It is not an unprimeable number, because it can be changed into a prime (257727133) 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, 21477256 + ... + 21477267.

It is an arithmetic number, because the mean of its divisors is an integer number (64431786).

Almost surely, 2^257727138 is an apocalyptic number.

257727138 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

257727138 is a wasteful number, since it uses less digits than its factorization.

257727138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42954528.

The product of its digits is 164640, while the sum is 42.

The square root of 257727138 is about 16053.8823341894. The cubic root of 257727138 is about 636.3851697587.

The spelling of 257727138 in words is "two hundred fifty-seven million, seven hundred twenty-seven thousand, one hundred thirty-eight".