309665664 has 192 divisors, whose sum is σ = 1111294080. Its totient is φ = 80409600.

The previous prime is 309665663. The next prime is 309665677. The reversal of 309665664 is 466566903.

It is a tau number, because it is divible by the number of its divisors (192).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309665663) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 86959 + ... + 90449.

It is an arithmetic number, because the mean of its divisors is an integer number (5787990).

Almost surely, 2^309665664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 309665664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (555647040).

309665664 is an abundant number, since it is smaller than the sum of its proper divisors (801628416).

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

309665664 is a wasteful number, since it uses less digits than its factorization.

309665664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3529 (or 3514 counting only the distinct ones).

The product of its (nonzero) digits is 699840, while the sum is 45.

The square root of 309665664 is about 17597.3197959235. The cubic root of 309665664 is about 676.5465509762.

The spelling of 309665664 in words is "three hundred nine million, six hundred sixty-five thousand, six hundred sixty-four".