256781366 has 8 divisors (see below), whose sum is σ = 385717440. Its totient is φ = 128208888.

The previous prime is 256781359. The next prime is 256781383. The reversal of 256781366 is 663187652.

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

It is a Curzon number.

It is a congruent 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, 89126 + ... + 91961.

It is an arithmetic number, because the mean of its divisors is an integer number (48214680).

Almost surely, 2^256781366 is an apocalyptic number.

256781366 is a deficient number, since it is larger than the sum of its proper divisors (128936074).

256781366 is a wasteful number, since it uses less digits than its factorization.

256781366 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 181798.

The product of its digits is 362880, while the sum is 44.

The square root of 256781366 is about 16024.3990838970. The cubic root of 256781366 is about 635.6057756926.

The spelling of 256781366 in words is "two hundred fifty-six million, seven hundred eighty-one thousand, three hundred sixty-six".