2105800321 has 9 divisors (see below), whose sum is σ = 2130357033. Its totient is φ = 2081525040.

The previous prime is 2105800283. The next prime is 2105800349. The reversal of 2105800321 is 1230085012.

The square root of 2105800321 is 45889.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 508998721 + 1596801600 = 22561^2 + 39960^2 .

It is not a de Polignac number, because 2105800321 - 2²⁹ = 1568929409 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2105800292 and 2105800301.

It is not an unprimeable number, because it can be changed into a prime (2105800391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5001691 + ... + 5002111.

It is an arithmetic number, because the mean of its divisors is an integer number (236706337).

Almost surely, 2^2105800321 is an apocalyptic number.

2105800321 is the 45889-th square number.

2105800321 is the 22945-th centered octagonal number.

It is an amenable number.

2105800321 is a deficient number, since it is larger than the sum of its proper divisors (24556712).

2105800321 is an frugal number, since it uses more digits than its factorization.

2105800321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1060 (or 530 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The cubic root of 2105800321 is about 1281.7570922977.

Adding to 2105800321 its reverse (1230085012), we get a palindrome (3335885333).

The spelling of 2105800321 in words is "two billion, one hundred five million, eight hundred thousand, three hundred twenty-one".