864503981 has 12 divisors (see below), whose sum is σ = 953707356. Its totient is φ = 783045120.

The previous prime is 864503963. The next prime is 864503993. The reversal of 864503981 is 189305468.

864503981 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 102191881 + 762312100 = 10109^2 + 27610^2 .

It is not a de Polignac number, because 864503981 - 2⁶ = 864503917 is a prime.

It is a super-2 number, since 2×864503981² = 1494734266329696722, which contains 22 as substring.

It is a hoax number, since the sum of its digits (44) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (864503581) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 20621 + ... + 46413.

It is an arithmetic number, because the mean of its divisors is an integer number (79475613).

Almost surely, 2^864503981 is an apocalyptic number.

It is an amenable number.

864503981 is a deficient number, since it is larger than the sum of its proper divisors (89203375).

864503981 is a wasteful number, since it uses less digits than its factorization.

864503981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26092 (or 26081 counting only the distinct ones).

The product of its (nonzero) digits is 207360, while the sum is 44.

The square root of 864503981 is about 29402.4485544997. The cubic root of 864503981 is about 952.6257849926.

The spelling of 864503981 in words is "eight hundred sixty-four million, five hundred three thousand, nine hundred eighty-one".