864339840 has 768 divisors, whose sum is σ = 3929627520. Its totient is φ = 169869312.

The previous prime is 864339821. The next prime is 864339893. The reversal of 864339840 is 48933468.

It is a super-2 number, since 2×864339840² = 1494166718022451200, which contains 22 as substring.

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 8910672 + ... + 8910768.

Almost surely, 2^864339840 is an apocalyptic number.

864339840 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 864339840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1964813760).

864339840 is an abundant number, since it is smaller than the sum of its proper divisors (3065287680).

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

864339840 is a wasteful number, since it uses less digits than its factorization.

864339840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 144 counting only the distinct ones).

The product of its (nonzero) digits is 497664, while the sum is 45.

The square root of 864339840 is about 29399.6571408580. The cubic root of 864339840 is about 952.5654903613.

The spelling of 864339840 in words is "eight hundred sixty-four million, three hundred thirty-nine thousand, eight hundred forty".