121212112011 has 4 divisors (see below), whose sum is σ = 161616149352.
Its totient is φ = 80808074672.
The previous prime is 121212112001. The next prime is 121212112019. The reversal of 121212112011 is 110211212121.
Adding to 121212112011 its reverse (110211212121), we get a palindrome (231423324132).
It is a happy number.
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 121212112011 - 26 = 121212111947 is a prime.
It is a super-3 number, since 3×1212121120113 (a number of 34 digits) contains 333 as substring.
It is not an unprimeable number, because it can be changed into a prime (121212112019) 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, 20202018666 + ... + 20202018671.
It is an arithmetic number, because the mean of its divisors is an integer number (40404037338).
Almost surely, 2121212112011 is an apocalyptic number.
121212112011 is a deficient number, since it is larger than the sum of its proper divisors (40404037341).
121212112011 is an equidigital number, since it uses as much as digits as its factorization.
121212112011 is an odious number, because the sum of its binary digits is odd.
The sum of its prime factors is 40404037340.
The product of its (nonzero) digits is 16, while the sum is 15.
The spelling of 121212112011 in words is "one hundred twenty-one billion, two hundred twelve million, one hundred twelve thousand, eleven".