11109191920 has 20 divisors (see below), whose sum is σ = 25828871400. Its totient is φ = 4443676736.

The previous prime is 11109191911. The next prime is 11109191927. The reversal of 11109191920 is 2919190111.

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11109191927) 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, 69432370 + ... + 69432529.

It is an arithmetic number, because the mean of its divisors is an integer number (1291443570).

Almost surely, 2^11109191920 is an apocalyptic number.

11109191920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

11109191920 is an abundant number, since it is smaller than the sum of its proper divisors (14719679480).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

11109191920 is a wasteful number, since it uses less digits than its factorization.

11109191920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 138864912 (or 138864906 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 34.

The spelling of 11109191920 in words is "eleven billion, one hundred nine million, one hundred ninety-one thousand, nine hundred twenty".