111111101920 has 192 divisors, whose sum is σ = 326279995776. Its totient is φ = 34816204800.

The previous prime is 111111101911. The next prime is 111111101921. The reversal of 111111101920 is 29101111111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111111101921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1432782 + ... + 1508338.

It is an arithmetic number, because the mean of its divisors is an integer number (1699374978).

Almost surely, 2^111111101920 is an apocalyptic number.

111111101920 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 111111101920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (163139997888).

111111101920 is an abundant number, since it is smaller than the sum of its proper divisors (215168893856).

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

111111101920 is a wasteful number, since it uses less digits than its factorization.

111111101920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 75693 (or 75685 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 19.

The spelling of 111111101920 in words is "one hundred eleven billion, one hundred eleven million, one hundred one thousand, nine hundred twenty".