256405029 has 4 divisors (see below), whose sum is σ = 341873376. Its totient is φ = 170936684.

The previous prime is 256405003. The next prime is 256405073. The reversal of 256405029 is 920504652.

256405029 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 256405029 - 2⁵ = 256404997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256400029) 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, 42734169 + ... + 42734174.

It is an arithmetic number, because the mean of its divisors is an integer number (85468344).

Almost surely, 2^256405029 is an apocalyptic number.

It is an amenable number.

256405029 is a deficient number, since it is larger than the sum of its proper divisors (85468347).

256405029 is an equidigital number, since it uses as much as digits as its factorization.

256405029 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85468346.

The product of its (nonzero) digits is 21600, while the sum is 33.

The square root of 256405029 is about 16012.6521538438. The cubic root of 256405029 is about 635.2951107258.

The spelling of 256405029 in words is "two hundred fifty-six million, four hundred five thousand, twenty-nine".