111990 has 16 divisors (see below), whose sum is σ = 268848. Its totient is φ = 29856.

The previous prime is 111977. The next prime is 111997. The reversal of 111990 is 99111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (111997) by changing a digit.

111990 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1837 + ... + 1896.

It is an arithmetic number, because the mean of its divisors is an integer number (16803).

2¹¹¹⁹⁹⁰ is an apocalyptic number.

111990 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

111990 is an abundant number, since it is smaller than the sum of its proper divisors (156858).

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

111990 is a wasteful number, since it uses less digits than its factorization.

111990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3743.

The product of its (nonzero) digits is 81, while the sum is 21.

The square root of 111990 is about 334.6490699225. The cubic root of 111990 is about 48.2014106323.

The spelling of 111990 in words is "one hundred eleven thousand, nine hundred ninety".