256389645 has 8 divisors (see below), whose sum is σ = 410223456. Its totient is φ = 136741136.

The previous prime is 256389641. The next prime is 256389659. The reversal of 256389645 is 546983652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256389645 - 2² = 256389641 is a prime.

It is a super-3 number, since 3×256389645³ (a number of 26 digits) contains 333 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 256389594 and 256389603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256389641) 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, 8546307 + ... + 8546336.

It is an arithmetic number, because the mean of its divisors is an integer number (51277932).

Almost surely, 2^256389645 is an apocalyptic number.

It is an amenable number.

256389645 is a deficient number, since it is larger than the sum of its proper divisors (153833811).

256389645 is a wasteful number, since it uses less digits than its factorization.

256389645 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17092651.

The product of its digits is 1555200, while the sum is 48.

The square root of 256389645 is about 16012.1717764955. The cubic root of 256389645 is about 635.2824048186.

The spelling of 256389645 in words is "two hundred fifty-six million, three hundred eighty-nine thousand, six hundred forty-five".