320720392 has 8 divisors (see below), whose sum is σ = 601350750. Its totient is φ = 160360192.

The previous prime is 320720381. The next prime is 320720417. The reversal of 320720392 is 293027023.

It can be written as a sum of positive squares in only one way, i.e., 308845476 + 11874916 = 17574^2 + 3446^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a hoax number, since the sum of its digits (28) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 320720392.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 20045017 + ... + 20045032.

Almost surely, 2^320720392 is an apocalyptic number.

It is an amenable number.

320720392 is a deficient number, since it is larger than the sum of its proper divisors (280630358).

320720392 is a wasteful number, since it uses less digits than its factorization.

320720392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40090055 (or 40090051 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 28.

The square root of 320720392 is about 17908.6680688431. The cubic root of 320720392 is about 684.5032660681.

The spelling of 320720392 in words is "three hundred twenty million, seven hundred twenty thousand, three hundred ninety-two".