257706320 has 40 divisors (see below), whose sum is σ = 613788840. Its totient is φ = 100567040.

The previous prime is 257706301. The next prime is 257706347. The reversal of 257706320 is 23607752.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 36529936 + 221176384 = 6044^2 + 14872^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36005 + ... + 42564.

It is an arithmetic number, because the mean of its divisors is an integer number (15344721).

Almost surely, 2^257706320 is an apocalyptic number.

257706320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

257706320 is an abundant number, since it is smaller than the sum of its proper divisors (356082520).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

257706320 is a wasteful number, since it uses less digits than its factorization.

257706320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 78623 (or 78617 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 32.

The square root of 257706320 is about 16053.2339421065. The cubic root of 257706320 is about 636.3680345522.

The spelling of 257706320 in words is "two hundred fifty-seven million, seven hundred six thousand, three hundred twenty".