12121121011 has 4 divisors (see below), whose sum is σ = 12326563800. Its totient is φ = 11915678224.

The previous prime is 12121121009. The next prime is 12121121029. The reversal of 12121121011 is 11012112121.

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 12121121011 - 2¹ = 12121121009 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12121120982 and 12121121000.

It is not an unprimeable number, because it can be changed into a prime (12121121081) 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, 102721306 + ... + 102721423.

It is an arithmetic number, because the mean of its divisors is an integer number (3081640950).

Almost surely, 2^12121121011 is an apocalyptic number.

12121121011 is a deficient number, since it is larger than the sum of its proper divisors (205442789).

12121121011 is an equidigital number, since it uses as much as digits as its factorization.

12121121011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205442788.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 12121121011 its reverse (11012112121), we get a palindrome (23133233132).

The spelling of 12121121011 in words is "twelve billion, one hundred twenty-one million, one hundred twenty-one thousand, eleven".