390664320 has 128 divisors (see below), whose sum is σ = 1310904000. Its totient is φ = 98684928.

The previous prime is 390664303. The next prime is 390664321. The reversal of 390664320 is 23466093.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×390664320² = 305237221842124800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (390664321) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 31126 + ... + 41834.

Almost surely, 2^390664320 is an apocalyptic number.

390664320 is a gapful number since it is divisible by the number (30) 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 390664320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (655452000).

390664320 is an abundant number, since it is smaller than the sum of its proper divisors (920239680).

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

390664320 is a wasteful number, since it uses less digits than its factorization.

390664320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10750 (or 10738 counting only the distinct ones).

The product of its (nonzero) digits is 23328, while the sum is 33.

The square root of 390664320 is about 19765.2300770823. The cubic root of 390664320 is about 731.0289611708.

The spelling of 390664320 in words is "three hundred ninety million, six hundred sixty-four thousand, three hundred twenty".