256812387 has 32 divisors (see below), whose sum is σ = 391728960. Its totient is φ = 148254720.

The previous prime is 256812349. The next prime is 256812419. The reversal of 256812387 is 783218652.

It is not a de Polignac number, because 256812387 - 2⁶ = 256812323 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256812317) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 337087 + ... + 337847.

It is an arithmetic number, because the mean of its divisors is an integer number (12241530).

Almost surely, 2^256812387 is an apocalyptic number.

256812387 is a deficient number, since it is larger than the sum of its proper divisors (134916573).

256812387 is a wasteful number, since it uses less digits than its factorization.

256812387 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1303.

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

The square root of 256812387 is about 16025.3669848774. The cubic root of 256812387 is about 635.6313698821.

The spelling of 256812387 in words is "two hundred fifty-six million, eight hundred twelve thousand, three hundred eighty-seven".