256400543 has 4 divisors (see below), whose sum is σ = 293029200. Its totient is φ = 219771888.

The previous prime is 256400539. The next prime is 256400549. The reversal of 256400543 is 345004652.

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

It is not a de Polignac number, because 256400543 - 2² = 256400539 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256400549) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 18314318 + ... + 18314331.

It is an arithmetic number, because the mean of its divisors is an integer number (73257300).

Almost surely, 2^256400543 is an apocalyptic number.

256400543 is a deficient number, since it is larger than the sum of its proper divisors (36628657).

256400543 is an equidigital number, since it uses as much as digits as its factorization.

256400543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36628656.

The product of its (nonzero) digits is 14400, while the sum is 29.

The square root of 256400543 is about 16012.5120764982. The cubic root of 256400543 is about 635.2914057146.

The spelling of 256400543 in words is "two hundred fifty-six million, four hundred thousand, five hundred forty-three".