256400553 has 8 divisors (see below), whose sum is σ = 341941600. Its totient is φ = 170896608.

The previous prime is 256400549. The next prime is 256400587. The reversal of 256400553 is 355004652.

256400553 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 not a de Polignac number, because 256400553 - 2² = 256400549 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256400553.

It is not an unprimeable number, because it can be changed into a prime (256400533) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20613 + ... + 30621.

It is an arithmetic number, because the mean of its divisors is an integer number (42742700).

Almost surely, 2^256400553 is an apocalyptic number.

It is an amenable number.

256400553 is a deficient number, since it is larger than the sum of its proper divisors (85541047).

256400553 is a wasteful number, since it uses less digits than its factorization.

256400553 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18551.

The product of its (nonzero) digits is 18000, while the sum is 30.

The square root of 256400553 is about 16012.5123887540. The cubic root of 256400553 is about 635.2914139737.

The spelling of 256400553 in words is "two hundred fifty-six million, four hundred thousand, five hundred fifty-three".