256932809 has 4 divisors (see below), whose sum is σ = 293637504. Its totient is φ = 220228116.

The previous prime is 256932803. The next prime is 256932827. The reversal of 256932809 is 908239652.

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 a de Polignac number, because none of the positive numbers 2^k-256932809 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 256932809.

It is not an unprimeable number, because it can be changed into a prime (256932803) 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, 18352337 + ... + 18352350.

It is an arithmetic number, because the mean of its divisors is an integer number (73409376).

Almost surely, 2^256932809 is an apocalyptic number.

It is an amenable number.

256932809 is a deficient number, since it is larger than the sum of its proper divisors (36704695).

256932809 is an equidigital number, since it uses as much as digits as its factorization.

256932809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36704694.

The product of its (nonzero) digits is 233280, while the sum is 44.

The square root of 256932809 is about 16029.1237751787. The cubic root of 256932809 is about 635.7307057445.

The spelling of 256932809 in words is "two hundred fifty-six million, nine hundred thirty-two thousand, eight hundred nine".