256403205 has 32 divisors (see below), whose sum is σ = 456693120. Its totient is φ = 136488960.

The previous prime is 256403179. The next prime is 256403209. The reversal of 256403205 is 502304652.

256403205 is a `hidden beast` number, since 2 + 56 + 403 + 205 = 666.

It is not a de Polignac number, because 256403205 - 2⁹ = 256402693 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256403209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 85054 + ... + 88016.

It is an arithmetic number, because the mean of its divisors is an integer number (14271660).

Almost surely, 2^256403205 is an apocalyptic number.

It is an amenable number.

256403205 is a deficient number, since it is larger than the sum of its proper divisors (200289915).

256403205 is a wasteful number, since it uses less digits than its factorization.

256403205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3618 (or 3612 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 27.

The square root of 256403205 is about 16012.5951987802. The cubic root of 256403205 is about 635.2936042797.

Adding to 256403205 its reverse (502304652), we get a palindrome (758707857).

The spelling of 256403205 in words is "two hundred fifty-six million, four hundred three thousand, two hundred five".