864615855 has 8 divisors (see below), whose sum is σ = 1383385392. Its totient is φ = 461128448.

The previous prime is 864615841. The next prime is 864615893. The reversal of 864615855 is 558516468.

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 864615855 - 2¹³ = 864607663 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28820514 + ... + 28820543.

It is an arithmetic number, because the mean of its divisors is an integer number (172923174).

Almost surely, 2^864615855 is an apocalyptic number.

864615855 is a deficient number, since it is larger than the sum of its proper divisors (518769537).

864615855 is a wasteful number, since it uses less digits than its factorization.

864615855 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 57641065.

The product of its digits is 1152000, while the sum is 48.

The square root of 864615855 is about 29404.3509535579. The cubic root of 864615855 is about 952.6668757847. Note that the first 3 decimals are identical.

The spelling of 864615855 in words is "eight hundred sixty-four million, six hundred fifteen thousand, eight hundred fifty-five".