121212211021111 has 4 divisors (see below), whose sum is σ = 138528241166992. Its totient is φ = 103896180875232.

The previous prime is 121212211021067. The next prime is 121212211021163. The reversal of 121212211021111 is 111120112212121.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 121212211021111 - 2⁹ = 121212211020599 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212011021111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8658015072930 + ... + 8658015072943.

It is an arithmetic number, because the mean of its divisors is an integer number (34632060291748).

Almost surely, 2^{121212211021111} is an apocalyptic number.

121212211021111 is a deficient number, since it is larger than the sum of its proper divisors (17316030145881).

121212211021111 is an equidigital number, since it uses as much as digits as its factorization.

121212211021111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17316030145880.

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

Adding to 121212211021111 its reverse (111120112212121), we get a palindrome (232332323233232).

The spelling of 121212211021111 in words is "one hundred twenty-one trillion, two hundred twelve billion, two hundred eleven million, twenty-one thousand, one hundred eleven".