212121110231 has 2 divisors, whose sum is σ = 212121110232. Its totient is φ = 212121110230.

The previous prime is 212121110219. The next prime is 212121110237. The reversal of 212121110231 is 132011121212.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-212121110231 is a prime.

It is a super-2 number, since 2×212121110231² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212121110237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060555115 + 106060555116.

It is an arithmetic number, because the mean of its divisors is an integer number (106060555116).

Almost surely, 2^212121110231 is an apocalyptic number.

212121110231 is a deficient number, since it is larger than the sum of its proper divisors (1).

212121110231 is an equidigital number, since it uses as much as digits as its factorization.

212121110231 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 212121110231 its reverse (132011121212), we get a palindrome (344132231443).

The spelling of 212121110231 in words is "two hundred twelve billion, one hundred twenty-one million, one hundred ten thousand, two hundred thirty-one".