12121012111 has 4 divisors (see below), whose sum is σ = 13053397672. Its totient is φ = 11188626552.

The previous prime is 12121012091. The next prime is 12121012139. The reversal of 12121012111 is 11121012121.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11121012121 = 23857 ⋅466153.

It is a cyclic number.

It is not a de Polignac number, because 12121012111 - 2¹⁷ = 12120881039 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (13), and also a Moran number because the ratio is a prime number: 932385547 = 12121012111 / (1 + 2 + 1 + 2 + 1 + 0 + 1 + 2 + 1 + 1 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12121012091 and 12121012100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121012511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 466192761 + ... + 466192786.

It is an arithmetic number, because the mean of its divisors is an integer number (3263349418).

Almost surely, 2^12121012111 is an apocalyptic number.

12121012111 is a deficient number, since it is larger than the sum of its proper divisors (932385561).

12121012111 is an equidigital number, since it uses as much as digits as its factorization.

12121012111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 932385560.

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

Adding to 12121012111 its reverse (11121012121), we get a palindrome (23242024232).

The spelling of 12121012111 in words is "twelve billion, one hundred twenty-one million, twelve thousand, one hundred eleven".