320021311 has 16 divisors (see below), whose sum is σ = 347575968. Its totient is φ = 293529600.

The previous prime is 320021297. The next prime is 320021363. The reversal of 320021311 is 113120023.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-320021311 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 320021291 and 320021300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (320021371) 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, 115816 + ... + 118546.

It is an arithmetic number, because the mean of its divisors is an integer number (21723498).

Almost surely, 2^320021311 is an apocalyptic number.

320021311 is a deficient number, since it is larger than the sum of its proper divisors (27554657).

320021311 is a wasteful number, since it uses less digits than its factorization.

320021311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2922.

The product of its (nonzero) digits is 36, while the sum is 13.

The square root of 320021311 is about 17889.1394706397. The cubic root of 320021311 is about 684.0055622075.

Adding to 320021311 its reverse (113120023), we get a palindrome (433141334).

The spelling of 320021311 in words is "three hundred twenty million, twenty-one thousand, three hundred eleven".