256380399 has 12 divisors (see below), whose sum is σ = 403993512. Its totient is φ = 155382000.

The previous prime is 256380367. The next prime is 256380401. The reversal of 256380399 is 993083652.

256380399 is a `hidden beast` number, since 2 + 5 + 638 + 0 + 3 + 9 + 9 = 666.

It is not a de Polignac number, because 256380399 - 2⁵ = 256380367 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256387399) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1294752 + ... + 1294949.

It is an arithmetic number, because the mean of its divisors is an integer number (33666126).

Almost surely, 2^256380399 is an apocalyptic number.

256380399 is a deficient number, since it is larger than the sum of its proper divisors (147613113).

256380399 is a wasteful number, since it uses less digits than its factorization.

256380399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2589718 (or 2589715 counting only the distinct ones).

The product of its (nonzero) digits is 349920, while the sum is 45.

The square root of 256380399 is about 16011.8830560306. The cubic root of 256380399 is about 635.2747681455.

The spelling of 256380399 in words is "two hundred fifty-six million, three hundred eighty thousand, three hundred ninety-nine".