864720 has 60 divisors (see below), whose sum is σ = 2906436. Its totient is φ = 230400.

The previous prime is 864707. The next prime is 864733. The reversal of 864720 is 27468.

It is an interprime number because it is at equal distance from previous prime (864707) and next prime (864733).

It can be written as a sum of positive squares in 2 ways, for example, as 97344 + 767376 = 312^2 + 876^2 .

It is a tau number, because it is divible by the number of its divisors (60).

It is a congruent number.

It is an unprimeable number.

864720 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 120 + ... + 1320.

2⁸⁶⁴⁷²⁰ is an apocalyptic number.

864720 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 864720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1453218).

864720 is an abundant number, since it is smaller than the sum of its proper divisors (2041716).

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

864720 is a wasteful number, since it uses less digits than its factorization.

864720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1220 (or 1211 counting only the distinct ones).

The product of its (nonzero) digits is 2688, while the sum is 27.

The square root of 864720 is about 929.9032207708. The cubic root of 864720 is about 95.2705124566.

The spelling of 864720 in words is "eight hundred sixty-four thousand, seven hundred twenty".