256781632 has 14 divisors (see below), whose sum is σ = 509551178. Its totient is φ = 128390784.

The previous prime is 256781621. The next prime is 256781641. The reversal of 256781632 is 236187652.

It can be written as a sum of positive squares in only one way, i.e., 250145856 + 6635776 = 15816^2 + 2576^2 .

It is an alternating number because its digits alternate between even and odd.

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 as a sum of consecutive naturals, namely, 2006043 + ... + 2006170.

Almost surely, 2^256781632 is an apocalyptic number.

It is an amenable number.

256781632 is a deficient number, since it is larger than the sum of its proper divisors (252769546).

256781632 is an equidigital number, since it uses as much as digits as its factorization.

256781632 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4012225 (or 4012215 counting only the distinct ones).

The product of its digits is 120960, while the sum is 40.

The square root of 256781632 is about 16024.4073837381. The cubic root of 256781632 is about 635.6059951673.

The spelling of 256781632 in words is "two hundred fifty-six million, seven hundred eighty-one thousand, six hundred thirty-two".