12121010191 has 4 divisors (see below), whose sum is σ = 12121230384. Its totient is φ = 12120790000.

The previous prime is 12121010179. The next prime is 12121010197. The reversal of 12121010191 is 19101012121.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 19101012121 = 1613 ⋅11841917.

It is a cyclic number.

It is not a de Polignac number, because 12121010191 - 2⁵ = 12121010159 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12121010197) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 54531 + ... + 164971.

It is an arithmetic number, because the mean of its divisors is an integer number (3030307596).

Almost surely, 2^12121010191 is an apocalyptic number.

12121010191 is a deficient number, since it is larger than the sum of its proper divisors (220193).

12121010191 is a wasteful number, since it uses less digits than its factorization.

12121010191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 220192.

The product of its (nonzero) digits is 36, while the sum is 19.

The spelling of 12121010191 in words is "twelve billion, one hundred twenty-one million, ten thousand, one hundred ninety-one".