256738 has 8 divisors (see below), whose sum is σ = 388332. Its totient is φ = 127296.

The previous prime is 256723. The next prime is 256757. The reversal of 256738 is 837652.

It can be written as a sum of positive squares in 2 ways, for example, as 243049 + 13689 = 493^2 + 117^2 .

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

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, 195 + ... + 742.

2²⁵⁶⁷³⁸ is an apocalyptic number.

256738 is a deficient number, since it is larger than the sum of its proper divisors (131594).

256738 is a wasteful number, since it uses less digits than its factorization.

256738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1076.

The product of its digits is 10080, while the sum is 31.

The square root of 256738 is about 506.6932010596. The cubic root of 256738 is about 63.5569992681.

The spelling of 256738 in words is "two hundred fifty-six thousand, seven hundred thirty-eight".