256863357493 has 12 divisors (see below), whose sum is σ = 266699684160. Its totient is φ = 247276729680.

The previous prime is 256863357481. The next prime is 256863357503. The reversal of 256863357493 is 394753368652.

It is not a de Polignac number, because 256863357493 - 2⁵ = 256863357461 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (61).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256863357473) 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, 559483 + ... + 909256.

It is an arithmetic number, because the mean of its divisors is an integer number (22224973680).

Almost surely, 2^256863357493 is an apocalyptic number.

It is an amenable number.

256863357493 is a deficient number, since it is larger than the sum of its proper divisors (9836326667).

256863357493 is an equidigital number, since it uses as much as digits as its factorization.

256863357493 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1468908 (or 1468847 counting only the distinct ones).

The product of its digits is 97977600, while the sum is 61.

The spelling of 256863357493 in words is "two hundred fifty-six billion, eight hundred sixty-three million, three hundred fifty-seven thousand, four hundred ninety-three".