257255905 has 8 divisors (see below), whose sum is σ = 314532072. Its totient is φ = 201921408.

The previous prime is 257255827. The next prime is 257255909. The reversal of 257255905 is 509552752.

It can be written as a sum of positive squares in 4 ways, for example, as 30813601 + 226442304 = 5551^2 + 15048^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 257255905 - 2⁷ = 257255777 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (257255909) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 485124 + ... + 485653.

It is an arithmetic number, because the mean of its divisors is an integer number (39316509).

Almost surely, 2^257255905 is an apocalyptic number.

It is an amenable number.

257255905 is a deficient number, since it is larger than the sum of its proper divisors (57276167).

257255905 is an equidigital number, since it uses as much as digits as its factorization.

257255905 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 970835.

The product of its (nonzero) digits is 157500, while the sum is 40.

The square root of 257255905 is about 16039.1990136665. The cubic root of 257255905 is about 635.9970737112.

The spelling of 257255905 in words is "two hundred fifty-seven million, two hundred fifty-five thousand, nine hundred five".