12111221001091 has 4 divisors (see below), whose sum is σ = 12113136430632. Its totient is φ = 12109305571552.

The previous prime is 12111221001071. The next prime is 12111221001097. The reversal of 12111221001091 is 19010012211121.

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 12111221001091 - 2⁴¹ = 9912197745539 is a prime.

It is a super-5 number, since 5×12111221001091⁵ (a number of 67 digits) contains 55555 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12111221001097) 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, 957705286 + ... + 957717931.

It is an arithmetic number, because the mean of its divisors is an integer number (3028284107658).

Almost surely, 2^{12111221001091} is an apocalyptic number.

12111221001091 is a deficient number, since it is larger than the sum of its proper divisors (1915429541).

12111221001091 is an equidigital number, since it uses as much as digits as its factorization.

12111221001091 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1915429540.

The product of its (nonzero) digits is 72, while the sum is 22.

The spelling of 12111221001091 in words is "twelve trillion, one hundred eleven billion, two hundred twenty-one million, one thousand, ninety-one".