2120310021 has 4 divisors (see below), whose sum is σ = 2827080032. Its totient is φ = 1413540012.

The previous prime is 2120310001. The next prime is 2120310043. The reversal of 2120310021 is 1200130212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 2120310021 - 2¹⁵ = 2120277253 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2120309979 and 2120310006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120310001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 353385001 + ... + 353385006.

It is an arithmetic number, because the mean of its divisors is an integer number (706770008).

Almost surely, 2^2120310021 is an apocalyptic number.

It is an amenable number.

2120310021 is a deficient number, since it is larger than the sum of its proper divisors (706770011).

2120310021 is an equidigital number, since it uses as much as digits as its factorization.

2120310021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 706770010.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 2120310021 is about 46046.8242227409. The cubic root of 2120310021 is about 1284.6942745960.

Adding to 2120310021 its reverse (1200130212), we get a palindrome (3320440233).

The spelling of 2120310021 in words is "two billion, one hundred twenty million, three hundred ten thousand, twenty-one".