256371387 has 4 divisors (see below), whose sum is σ = 341828520. Its totient is φ = 170914256.

The previous prime is 256371383. The next prime is 256371419. The reversal of 256371387 is 783173652.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 256371387 - 2² = 256371383 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256371383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 42728562 + ... + 42728567.

It is an arithmetic number, because the mean of its divisors is an integer number (85457130).

Almost surely, 2^256371387 is an apocalyptic number.

256371387 is a deficient number, since it is larger than the sum of its proper divisors (85457133).

256371387 is an equidigital number, since it uses as much as digits as its factorization.

256371387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85457132.

The product of its digits is 211680, while the sum is 42.

The square root of 256371387 is about 16011.6016375627. The cubic root of 256371387 is about 635.2673245665.

The spelling of 256371387 in words is "two hundred fifty-six million, three hundred seventy-one thousand, three hundred eighty-seven".