2121313231 has 2 divisors, whose sum is σ = 2121313232. Its totient is φ = 2121313230.

The previous prime is 2121313223. The next prime is 2121313237. The reversal of 2121313231 is 1323131212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 2121313231 - 2³ = 2121313223 is a prime.

It is a super-2 number, since 2×2121313231² = 8999939648031318722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 2121313199 and 2121313208.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121313237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060656615 + 1060656616.

It is an arithmetic number, because the mean of its divisors is an integer number (1060656616).

Almost surely, 2^2121313231 is an apocalyptic number.

2121313231 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121313231 is an equidigital number, since it uses as much as digits as its factorization.

2121313231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 216, while the sum is 19.

The square root of 2121313231 is about 46057.7163024829. The cubic root of 2121313231 is about 1284.8968573817.

Adding to 2121313231 its reverse (1323131212), we get a palindrome (3444444443).

The spelling of 2121313231 in words is "two billion, one hundred twenty-one million, three hundred thirteen thousand, two hundred thirty-one".