256873778 has 18 divisors (see below), whose sum is σ = 448495551. Its totient is φ = 110020764.

The previous prime is 256873763. The next prime is 256873829. The reversal of 256873778 is 877378652.

It can be written as a sum of positive squares in only one way, i.e., 128436889 + 128436889 = 11333^2 + 11333^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=11333.

It is an unprimeable number.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 157853 + ... + 159471.

Almost surely, 2^256873778 is an apocalyptic number.

256873778 is a deficient number, since it is larger than the sum of its proper divisors (191621773).

256873778 is an frugal number, since it uses more digits than its factorization.

256873778 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3254 (or 1628 counting only the distinct ones).

The product of its digits is 3951360, while the sum is 53.

The square root of 256873778 is about 16027.2823023743. The cubic root of 256873778 is about 635.6820150721.

The spelling of 256873778 in words is "two hundred fifty-six million, eight hundred seventy-three thousand, seven hundred seventy-eight".