256406645 has 16 divisors (see below), whose sum is σ = 350255232. Its totient is φ = 178368960.

The previous prime is 256406639. The next prime is 256406663. The reversal of 256406645 is 546604652.

It is not a de Polignac number, because 256406645 - 2⁴ = 256406629 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 256406599 and 256406608.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 100082 + ... + 102611.

It is an arithmetic number, because the mean of its divisors is an integer number (21890952).

Almost surely, 2^256406645 is an apocalyptic number.

It is an amenable number.

256406645 is a deficient number, since it is larger than the sum of its proper divisors (93848587).

256406645 is a wasteful number, since it uses less digits than its factorization.

256406645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 202732.

The product of its (nonzero) digits is 172800, while the sum is 38.

The square root of 256406645 is about 16012.7026138625. The cubic root of 256406645 is about 635.2964453781.

The spelling of 256406645 in words is "two hundred fifty-six million, four hundred six thousand, six hundred forty-five".