2121031313 has 6 divisors (see below), whose sum is σ = 2238540354. Its totient is φ = 2009397744.

The previous prime is 2121031301. The next prime is 2121031321. The reversal of 2121031313 is 3131301212.

It can be written as a sum of positive squares in only one way, i.e., 1938024529 + 183006784 = 44023^2 + 13528^2 .

It is not a de Polignac number, because 2121031313 - 2⁸ = 2121031057 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2121031291 and 2121031300.

It is not an unprimeable number, because it can be changed into a prime (2121031343) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2937356 + ... + 2938077.

It is an arithmetic number, because the mean of its divisors is an integer number (373090059).

Almost surely, 2^2121031313 is an apocalyptic number.

It is an amenable number.

2121031313 is a deficient number, since it is larger than the sum of its proper divisors (117509041).

2121031313 is an equidigital number, since it uses as much as digits as its factorization.

2121031313 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5875471 (or 5875452 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 2121031313 is about 46054.6557147049. The cubic root of 2121031313 is about 1284.8399348435.

Adding to 2121031313 its reverse (3131301212), we get a palindrome (5252332525).

The spelling of 2121031313 in words is "two billion, one hundred twenty-one million, thirty-one thousand, three hundred thirteen".