257386 has 4 divisors (see below), whose sum is σ = 386082. Its totient is φ = 128692.

The previous prime is 257381. The next prime is 257399. The reversal of 257386 is 683752.

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

It can be written as a sum of positive squares in only one way, i.e., 145161 + 112225 = 381^2 + 335^2 .

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an Ulam number.

It is a nialpdrome in base 8.

It is not an unprimeable number, because it can be changed into a prime (257381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64345 + ... + 64348.

2²⁵⁷³⁸⁶ is an apocalyptic number.

257386 is a deficient number, since it is larger than the sum of its proper divisors (128696).

257386 is a wasteful number, since it uses less digits than its factorization.

257386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 128695.

The product of its digits is 10080, while the sum is 31.

The square root of 257386 is about 507.3322382818. The cubic root of 257386 is about 63.6104264119.

The spelling of 257386 in words is "two hundred fifty-seven thousand, three hundred eighty-six".