2121121231 has 2 divisors, whose sum is σ = 2121121232. Its totient is φ = 2121121230.

The previous prime is 2121121217. The next prime is 2121121271. The reversal of 2121121231 is 1321211212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 2121121231 - 2⁵ = 2121121199 is a prime.

It is a super-2 number, since 2×2121121231² = 8998310553197910722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121121201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060560615 + 1060560616.

It is an arithmetic number, because the mean of its divisors is an integer number (1060560616).

Almost surely, 2^2121121231 is an apocalyptic number.

2121121231 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121121231 is an equidigital number, since it uses as much as digits as its factorization.

2121121231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48, while the sum is 16.

The square root of 2121121231 is about 46055.6319140233. The cubic root of 2121121231 is about 1284.8580908861.

Adding to 2121121231 its reverse (1321211212), we get a palindrome (3442332443).

The spelling of 2121121231 in words is "two billion, one hundred twenty-one million, one hundred twenty-one thousand, two hundred thirty-one".