8664720 has 80 divisors (see below), whose sum is σ = 27260160. Its totient is φ = 2276352.

The previous prime is 8664701. The next prime is 8664731. The reversal of 8664720 is 274668.

It is a tau number, because it is divible by the number of its divisors (80).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18732 + ... + 19188.

It is an arithmetic number, because the mean of its divisors is an integer number (340752).

Almost surely, 2^8664720 is an apocalyptic number.

8664720 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 8664720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (13630080).

8664720 is an abundant number, since it is smaller than the sum of its proper divisors (18595440).

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

8664720 is a wasteful number, since it uses less digits than its factorization.

8664720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 552 (or 546 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 33.

The square root of 8664720 is about 2943.5896453140. The cubic root of 8664720 is about 205.3926245073.

The spelling of 8664720 in words is "eight million, six hundred sixty-four thousand, seven hundred twenty".