665288704 has 64 divisors (see below), whose sum is σ = 1352642400. Its totient is φ = 327155712.

The previous prime is 665288683. The next prime is 665288707. The reversal of 665288704 is 407882566.

It is a tau number, because it is divible by the number of its divisors (64).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665288707) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2588544 + ... + 2588800.

Almost surely, 2^665288704 is an apocalyptic number.

665288704 is a gapful number since it is divisible by the number (64) 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 665288704, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (676321200).

665288704 is an abundant number, since it is smaller than the sum of its proper divisors (687353696).

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

665288704 is an frugal number, since it uses more digits than its factorization.

665288704 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 366 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 645120, while the sum is 46.

The square root of 665288704 is about 25793.1910394972. The cubic root of 665288704 is about 872.9781689416.

The spelling of 665288704 in words is "six hundred sixty-five million, two hundred eighty-eight thousand, seven hundred four".