256720782 has 16 divisors (see below), whose sum is σ = 518735952. Its totient is φ = 84691200.

The previous prime is 256720769. The next prime is 256720787. The reversal of 256720782 is 287027652.

It is a self number, because there is not a number n which added to its sum of digits gives 256720782.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256720787) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 219969 + ... + 221132.

It is an arithmetic number, because the mean of its divisors is an integer number (32420997).

Almost surely, 2^256720782 is an apocalyptic number.

256720782 is an abundant number, since it is smaller than the sum of its proper divisors (262015170).

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

256720782 is a wasteful number, since it uses less digits than its factorization.

256720782 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441203.

The product of its (nonzero) digits is 94080, while the sum is 39.

The square root of 256720782 is about 16022.5086050843. The cubic root of 256720782 is about 635.5557843066. Note that the first 3 decimals are identical.

The spelling of 256720782 in words is "two hundred fifty-six million, seven hundred twenty thousand, seven hundred eighty-two".