864438720 has 168 divisors, whose sum is σ = 2839010832. Its totient is φ = 222842880.

The previous prime is 864438719. The next prime is 864438721. The reversal of 864438720 is 27834468.

864438720 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (864438719) and next prime (864438721).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (864438721) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 922092 + ... + 923028.

It is an arithmetic number, because the mean of its divisors is an integer number (16898874).

Almost surely, 2^864438720 is an apocalyptic number.

864438720 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 864438720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1419505416).

864438720 is an abundant number, since it is smaller than the sum of its proper divisors (1974572112).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

864438720 is a wasteful number, since it uses less digits than its factorization.

864438720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019 (or 978 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The square root of 864438720 is about 29401.3387450300. The cubic root of 864438720 is about 952.6018132982.

The spelling of 864438720 in words is "eight hundred sixty-four million, four hundred thirty-eight thousand, seven hundred twenty".