256540065533 has 8 divisors (see below), whose sum is σ = 257506941888. Its totient is φ = 255575003104.

The previous prime is 256540065511. The next prime is 256540065557. The reversal of 256540065533 is 335560045652.

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 256540065533 - 2²⁶ = 256472956669 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256540065503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 169760 + ... + 736137.

It is an arithmetic number, because the mean of its divisors is an integer number (32188367736).

Almost surely, 2^256540065533 is an apocalyptic number.

It is an amenable number.

256540065533 is a deficient number, since it is larger than the sum of its proper divisors (966876355).

256540065533 is an equidigital number, since it uses as much as digits as its factorization.

256540065533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 906963.

The product of its (nonzero) digits is 1620000, while the sum is 44.

The spelling of 256540065533 in words is "two hundred fifty-six billion, five hundred forty million, sixty-five thousand, five hundred thirty-three".