256558550389 has 4 divisors (see below), whose sum is σ = 257991838560. Its totient is φ = 255125262220.

The previous prime is 256558550371. The next prime is 256558550441. The reversal of 256558550389 is 983055855652.

It is a happy number.

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 not a de Polignac number, because 256558550389 - 2¹³ = 256558542197 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 (256558550489) 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, 716643817 + ... + 716644174.

It is an arithmetic number, because the mean of its divisors is an integer number (64497959640).

Almost surely, 2^256558550389 is an apocalyptic number.

It is an amenable number.

256558550389 is a deficient number, since it is larger than the sum of its proper divisors (1433288171).

256558550389 is a wasteful number, since it uses less digits than its factorization.

256558550389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1433288170.

The product of its (nonzero) digits is 64800000, while the sum is 61.

The spelling of 256558550389 in words is "two hundred fifty-six billion, five hundred fifty-eight million, five hundred fifty thousand, three hundred eighty-nine".