1991112 has 16 divisors (see below), whose sum is σ = 4977840. Its totient is φ = 663696.

The previous prime is 1991107. The next prime is 1991123. The reversal of 1991112 is 2111991.

It is a Harshad number since it is a multiple of its sum of digits (24), and also a Moran number because the ratio is a prime number: 82963 = 1991112 / (1 + 9 + 9 + 1 + 1 + 1 + 2).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41458 + ... + 41505.

It is an arithmetic number, because the mean of its divisors is an integer number (311115).

2^1991112 is an apocalyptic number.

1991112 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

1991112 is an abundant number, since it is smaller than the sum of its proper divisors (2986728).

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

1991112 is a wasteful number, since it uses less digits than its factorization.

1991112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82972 (or 82968 counting only the distinct ones).

The product of its digits is 162, while the sum is 24.

The square root of 1991112 is about 1411.0676808715. The cubic root of 1991112 is about 125.8051915294.

The spelling of 1991112 in words is "one million, nine hundred ninety-one thousand, one hundred twelve".