121212111213 has 48 divisors (see below), whose sum is σ = 187536890736. Its totient is φ = 75173683200.

The previous prime is 121212111169. The next prime is 121212111227. The reversal of 121212111213 is 312111212121.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 19321556004 + 101890555209 = 139002^2 + 319203^2 .

It is not a de Polignac number, because 121212111213 - 2²⁴ = 121195333997 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121212111283) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 9528145 + ... + 9540857.

It is an arithmetic number, because the mean of its divisors is an integer number (3907018557).

Almost surely, 2^121212111213 is an apocalyptic number.

It is an amenable number.

121212111213 is a deficient number, since it is larger than the sum of its proper divisors (66324779523).

121212111213 is a wasteful number, since it uses less digits than its factorization.

121212111213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13454 (or 13451 counting only the distinct ones).

The product of its digits is 48, while the sum is 18.

Adding to 121212111213 its reverse (312111212121), we get a palindrome (433323323334).

The spelling of 121212111213 in words is "one hundred twenty-one billion, two hundred twelve million, one hundred eleven thousand, two hundred thirteen".