2131320321 has 12 divisors (see below), whose sum is σ = 3315387348. Its totient is φ = 1311581664.

The previous prime is 2131320283. The next prime is 2131320341. The reversal of 2131320321 is 1230231312.

2131320321 is a `hidden beast` number, since 21 + 3 + 1 + 320 + 321 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 1336926096 + 794394225 = 36564^2 + 28185^2 .

It is not a de Polignac number, because 2131320321 - 2¹⁵ = 2131287553 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2131320294 and 2131320303.

It is not an unprimeable number, because it can be changed into a prime (2131320341) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9108090 + ... + 9108323.

It is an arithmetic number, because the mean of its divisors is an integer number (276282279).

Almost surely, 2^2131320321 is an apocalyptic number.

It is an amenable number.

2131320321 is a deficient number, since it is larger than the sum of its proper divisors (1184067027).

2131320321 is a wasteful number, since it uses less digits than its factorization.

2131320321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18216432 (or 18216429 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

The square root of 2131320321 is about 46166.2248943966. The cubic root of 2131320321 is about 1286.9141474600.

Adding to 2131320321 its reverse (1230231312), we get a palindrome (3361551633).

The spelling of 2131320321 in words is "two billion, one hundred thirty-one million, three hundred twenty thousand, three hundred twenty-one".