257555 has 4 divisors (see below), whose sum is σ = 309072. Its totient is φ = 206040.

The previous prime is 257539. The next prime is 257561. The reversal of 257555 is 555752.

257555 = T₂₉₀ + T₂₉₁ + ... + T₂₉₅.

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

It is not a de Polignac number, because 257555 - 2⁴ = 257539 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25751 + ... + 25760.

It is an arithmetic number, because the mean of its divisors is an integer number (77268).

2²⁵⁷⁵⁵⁵ is an apocalyptic number.

257555 is a deficient number, since it is larger than the sum of its proper divisors (51517).

257555 is an equidigital number, since it uses as much as digits as its factorization.

257555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51516.

The product of its digits is 8750, while the sum is 29.

The square root of 257555 is about 507.4987684714. The cubic root of 257555 is about 63.6243455969.

The spelling of 257555 in words is "two hundred fifty-seven thousand, five hundred fifty-five".