256218738 has 16 divisors (see below), whose sum is σ = 512684640. Its totient is φ = 85365056.

The previous prime is 256218733. The next prime is 256218773. The reversal of 256218738 is 837812652.

It is a self number, because there is not a number n which added to its sum of digits gives 256218738.

It is not an unprimeable number, because it can be changed into a prime (256218731) 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, 4906 + ... + 23162.

It is an arithmetic number, because the mean of its divisors is an integer number (32042790).

Almost surely, 2^256218738 is an apocalyptic number.

256218738 is an abundant number, since it is smaller than the sum of its proper divisors (256465902).

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

256218738 is a wasteful number, since it uses less digits than its factorization.

256218738 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20601.

The product of its digits is 161280, while the sum is 42.

The square root of 256218738 is about 16006.8341029699. The cubic root of 256218738 is about 635.1412156223.

The spelling of 256218738 in words is "two hundred fifty-six million, two hundred eighteen thousand, seven hundred thirty-eight".