256553585949 has 4 divisors (see below), whose sum is σ = 342071447936. Its totient is φ = 171035723964.

The previous prime is 256553585927. The next prime is 256553585983. The reversal of 256553585949 is 949585355652.

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 not a de Polignac number, because 256553585949 - 2¹² = 256553581853 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 256553585949.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256553585549) 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, 42758930989 + ... + 42758930994.

It is an arithmetic number, because the mean of its divisors is an integer number (85517861984).

Almost surely, 2^256553585949 is an apocalyptic number.

It is an amenable number.

256553585949 is a deficient number, since it is larger than the sum of its proper divisors (85517861987).

256553585949 is an equidigital number, since it uses as much as digits as its factorization.

256553585949 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 85517861986.

The product of its digits is 291600000, while the sum is 66.

The spelling of 256553585949 in words is "two hundred fifty-six billion, five hundred fifty-three million, five hundred eighty-five thousand, nine hundred forty-nine".