257655 has 16 divisors (see below), whose sum is σ = 419040. Its totient is φ = 135168.

The previous prime is 257639. The next prime is 257657. The reversal of 257655 is 556752.

257655 = 225² + 226² + ... + 229².

It is not a de Polignac number, because 257655 - 2⁴ = 257639 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (257657) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1239 + ... + 1431.

It is an arithmetic number, because the mean of its divisors is an integer number (26190).

2²⁵⁷⁶⁵⁵ is an apocalyptic number.

257655 is a deficient number, since it is larger than the sum of its proper divisors (161385).

257655 is a wasteful number, since it uses less digits than its factorization.

257655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 290.

The product of its digits is 10500, while the sum is 30.

The square root of 257655 is about 507.5972813166. The cubic root of 257655 is about 63.6325789338.

The spelling of 257655 in words is "two hundred fifty-seven thousand, six hundred fifty-five".