257155 has 4 divisors (see below), whose sum is σ = 308592. Its totient is φ = 205720.

The previous prime is 257141. The next prime is 257161. The reversal of 257155 is 551752.

It is a happy number.

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

It is not a de Polignac number, because 257155 - 2⁵ = 257123 is a prime.

It is a super-2 number, since 2×257155² = 132257388050, which contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 25711 + ... + 25720.

It is an arithmetic number, because the mean of its divisors is an integer number (77148).

2²⁵⁷¹⁵⁵ is an apocalyptic number.

257155 is a deficient number, since it is larger than the sum of its proper divisors (51437).

257155 is an equidigital number, since it uses as much as digits as its factorization.

257155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51436.

The product of its digits is 1750, while the sum is 25.

The square root of 257155 is about 507.1045257144. The cubic root of 257155 is about 63.5913909210.

The spelling of 257155 in words is "two hundred fifty-seven thousand, one hundred fifty-five".