212121111220111 has 2 divisors, whose sum is σ = 212121111220112. Its totient is φ = 212121111220110.

The previous prime is 212121111220049. The next prime is 212121111220147. The reversal of 212121111220111 is 111022111121212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 212121111220111 - 2⁴¹ = 209922087964559 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (212121111220181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106060555610055 + 106060555610056.

It is an arithmetic number, because the mean of its divisors is an integer number (106060555610056).

Almost surely, 2^{212121111220111} is an apocalyptic number.

212121111220111 is a deficient number, since it is larger than the sum of its proper divisors (1).

212121111220111 is an equidigital number, since it uses as much as digits as its factorization.

212121111220111 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32, while the sum is 19.

Adding to 212121111220111 its reverse (111022111121212), we get a palindrome (323143222341323).

The spelling of 212121111220111 in words is "two hundred twelve trillion, one hundred twenty-one billion, one hundred eleven million, two hundred twenty thousand, one hundred eleven".