864561590 has 16 divisors (see below), whose sum is σ = 1556575488. Its totient is φ = 345743616.

The previous prime is 864561563. The next prime is 864561619. The reversal of 864561590 is 95165468.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54059 + ... + 68201.

It is an arithmetic number, because the mean of its divisors is an integer number (97285968).

Almost surely, 2^864561590 is an apocalyptic number.

864561590 is a deficient number, since it is larger than the sum of its proper divisors (692013898).

864561590 is a wasteful number, since it uses less digits than its factorization.

864561590 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20263.

The product of its (nonzero) digits is 259200, while the sum is 44.

The square root of 864561590 is about 29403.4282014870. The cubic root of 864561590 is about 952.6469449491.

The spelling of 864561590 in words is "eight hundred sixty-four million, five hundred sixty-one thousand, five hundred ninety".