320639340 has 144 divisors (see below), whose sum is σ = 1051674624. Its totient is φ = 72777600.

The previous prime is 320639323. The next prime is 320639359. The reversal of 320639340 is 43936023.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a junction number, because it is equal to n+sod(n) for n = 320639298 and 320639307.

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 in 47 ways as a sum of consecutive naturals, for example, 561255 + ... + 561825.

It is an arithmetic number, because the mean of its divisors is an integer number (7303296).

Almost surely, 2^320639340 is an apocalyptic number.

320639340 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 320639340, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (525837312).

320639340 is an abundant number, since it is smaller than the sum of its proper divisors (731035284).

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

320639340 is a wasteful number, since it uses less digits than its factorization.

320639340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 788 (or 779 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 30.

The square root of 320639340 is about 17906.4049993292. The cubic root of 320639340 is about 684.4455989803.

The spelling of 320639340 in words is "three hundred twenty million, six hundred thirty-nine thousand, three hundred forty".