256811345 has 8 divisors (see below), whose sum is σ = 352198464. Its totient is φ = 176099184.

The previous prime is 256811329. The next prime is 256811377. The reversal of 256811345 is 543118652.

256811345 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256811345 - 2⁴ = 256811329 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (35), and also a Moran number because the ratio is a prime number: 7337467 = 256811345 / (2 + 5 + 6 + 8 + 1 + 1 + 3 + 4 + 5).

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3668699 + ... + 3668768.

It is an arithmetic number, because the mean of its divisors is an integer number (44024808).

Almost surely, 2^256811345 is an apocalyptic number.

It is an amenable number.

256811345 is a deficient number, since it is larger than the sum of its proper divisors (95387119).

256811345 is an equidigital number, since it uses as much as digits as its factorization.

256811345 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7337479.

The product of its digits is 28800, while the sum is 35.

The square root of 256811345 is about 16025.3344738885. The cubic root of 256811345 is about 635.6305102029.

Adding to 256811345 its reverse (543118652), we get a palindrome (799929997).

The spelling of 256811345 in words is "two hundred fifty-six million, eight hundred eleven thousand, three hundred forty-five".