864663555 has 64 divisors (see below), whose sum is σ = 1653120000. Its totient is φ = 385539840.

The previous prime is 864663551. The next prime is 864663577. The reversal of 864663555 is 555366468.

It is not a de Polignac number, because 864663555 - 2² = 864663551 is a prime.

It is not an unprimeable number, because it can be changed into a prime (864663551) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 208896 + ... + 212994.

It is an arithmetic number, because the mean of its divisors is an integer number (25830000).

Almost surely, 2^864663555 is an apocalyptic number.

864663555 is a deficient number, since it is larger than the sum of its proper divisors (788456445).

864663555 is a wasteful number, since it uses less digits than its factorization.

864663555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4169 (or 4155 counting only the distinct ones).

The product of its digits is 2592000, while the sum is 48.

The square root of 864663555 is about 29405.1620468244. The cubic root of 864663555 is about 952.6843946918.

The spelling of 864663555 in words is "eight hundred sixty-four million, six hundred sixty-three thousand, five hundred fifty-five".