256996387 has 2 divisors, whose sum is σ = 256996388. Its totient is φ = 256996386.

The previous prime is 256996381. The next prime is 256996403. The reversal of 256996387 is 783699652.

256996387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 256996387 - 2³ = 256996379 is a prime.

It is not a weakly prime, because it can be changed into another prime (256996381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128498193 + 128498194.

It is an arithmetic number, because the mean of its divisors is an integer number (128498194).

Almost surely, 2^256996387 is an apocalyptic number.

256996387 is a deficient number, since it is larger than the sum of its proper divisors (1).

256996387 is an equidigital number, since it uses as much as digits as its factorization.

256996387 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4898880, while the sum is 55.

The square root of 256996387 is about 16031.1068551114. The cubic root of 256996387 is about 635.7831385882.

The spelling of 256996387 in words is "two hundred fifty-six million, nine hundred ninety-six thousand, three hundred eighty-seven".