11921541109 has 4 divisors (see below), whose sum is σ = 11926954816. Its totient is φ = 11916127404.

The previous prime is 11921541103. The next prime is 11921541157. The reversal of 11921541109 is 90114512911.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 11921541109 - 2³ = 11921541101 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 (11921541101) 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, 2703549 + ... + 2707954.

It is an arithmetic number, because the mean of its divisors is an integer number (2981738704).

Almost surely, 2^11921541109 is an apocalyptic number.

It is an amenable number.

11921541109 is a deficient number, since it is larger than the sum of its proper divisors (5413707).

11921541109 is an equidigital number, since it uses as much as digits as its factorization.

11921541109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5413706.

The product of its (nonzero) digits is 3240, while the sum is 34.

The spelling of 11921541109 in words is "eleven billion, nine hundred twenty-one million, five hundred forty-one thousand, one hundred nine".