2102320021 has 2 divisors, whose sum is σ = 2102320022. Its totient is φ = 2102320020.

The previous prime is 2102319979. The next prime is 2102320063. The reversal of 2102320021 is 1200232012.

It is a balanced prime because it is at equal distance from previous prime (2102319979) and next prime (2102320063).

It can be written as a sum of positive squares in only one way, i.e., 1280637796 + 821682225 = 35786^2 + 28665^2 .

It is a cyclic number.

It is not a de Polignac number, because 2102320021 - 2¹⁹ = 2101795733 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2102319983 and 2102320010.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2102320921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1051160010 + 1051160011.

It is an arithmetic number, because the mean of its divisors is an integer number (1051160011).

Almost surely, 2^2102320021 is an apocalyptic number.

It is an amenable number.

2102320021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2102320021 is an equidigital number, since it uses as much as digits as its factorization.

2102320021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 48, while the sum is 13.

The square root of 2102320021 is about 45851.0634664017. The cubic root of 2102320021 is about 1281.0505740580.

Adding to 2102320021 its reverse (1200232012), we get a palindrome (3302552033).

The spelling of 2102320021 in words is "two billion, one hundred two million, three hundred twenty thousand, twenty-one".