111811980 has 96 divisors (see below), whose sum is σ = 364621824. Its totient is φ = 25069824.

The previous prime is 111811967. The next prime is 111812053. The reversal of 111811980 is 89118111.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 19749 + ... + 24771.

It is an arithmetic number, because the mean of its divisors is an integer number (3798144).

Almost surely, 2^111811980 is an apocalyptic number.

111811980 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 111811980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (182310912).

111811980 is an abundant number, since it is smaller than the sum of its proper divisors (252809844).

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

111811980 is a wasteful number, since it uses less digits than its factorization.

111811980 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5095 (or 5093 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 30.

The square root of 111811980 is about 10574.1184029686. The cubic root of 111811980 is about 481.7585666665.

The spelling of 111811980 in words is "one hundred eleven million, eight hundred eleven thousand, nine hundred eighty".