121212220211 has 4 divisors (see below), whose sum is σ = 121755772992. Its totient is φ = 120668667432.

The previous prime is 121212220201. The next prime is 121212220243. The reversal of 121212220211 is 112022212121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 112022212121 = 124133 ⋅902437.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-121212220211 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 121212220211.

It is not an unprimeable number, because it can be changed into a prime (121212220201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 271776056 + ... + 271776501.

It is an arithmetic number, because the mean of its divisors is an integer number (30438943248).

Almost surely, 2^121212220211 is an apocalyptic number.

121212220211 is a deficient number, since it is larger than the sum of its proper divisors (543552781).

121212220211 is an equidigital number, since it uses as much as digits as its factorization.

121212220211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 543552780.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 121212220211 its reverse (112022212121), we get a palindrome (233234432332).

The spelling of 121212220211 in words is "one hundred twenty-one billion, two hundred twelve million, two hundred twenty thousand, two hundred eleven".