12011220191 has 4 divisors (see below), whose sum is σ = 12011839392. Its totient is φ = 12010600992.

The previous prime is 12011220187. The next prime is 12011220197. The reversal of 12011220191 is 19102211021.

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 12011220191 - 2² = 12011220187 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 (12011220197) 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, 279530 + ... + 319623.

It is an arithmetic number, because the mean of its divisors is an integer number (3002959848).

Almost surely, 2^12011220191 is an apocalyptic number.

12011220191 is a deficient number, since it is larger than the sum of its proper divisors (619201).

12011220191 is an equidigital number, since it uses as much as digits as its factorization.

12011220191 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 619200.

The product of its (nonzero) digits is 72, while the sum is 20.

The spelling of 12011220191 in words is "twelve billion, eleven million, two hundred twenty thousand, one hundred ninety-one".