121211211211 has 4 divisors (see below), whose sum is σ = 124030076632. Its totient is φ = 118392345792.

The previous prime is 121211211193. The next prime is 121211211217. The reversal of 121211211211 is 112112112121.

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 121211211211 - 2⁷ = 121211211083 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (121211211217) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1409432646 + ... + 1409432731.

It is an arithmetic number, because the mean of its divisors is an integer number (31007519158).

Almost surely, 2^121211211211 is an apocalyptic number.

121211211211 is a deficient number, since it is larger than the sum of its proper divisors (2818865421).

121211211211 is an equidigital number, since it uses as much as digits as its factorization.

121211211211 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2818865420.

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

Adding to 121211211211 its reverse (112112112121), we get a palindrome (233323323332).

It can be divided in two parts, 1 and 21211211211, that added together give a palindrome (21211211212).

The spelling of 121211211211 in words is "one hundred twenty-one billion, two hundred eleven million, two hundred eleven thousand, two hundred eleven".