1991086 has 16 divisors (see below), whose sum is σ = 3173760. Its totient is φ = 934200.

The previous prime is 1991071. The next prime is 1991089. The reversal of 1991086 is 6801991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1991089) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5565 + ... + 5911.

It is an arithmetic number, because the mean of its divisors is an integer number (198360).

2^1991086 is an apocalyptic number.

1991086 is a deficient number, since it is larger than the sum of its proper divisors (1182674).

1991086 is a wasteful number, since it uses less digits than its factorization.

1991086 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 519.

The product of its (nonzero) digits is 3888, while the sum is 34.

The square root of 1991086 is about 1411.0584679594. The cubic root of 1991086 is about 125.8046439377.

The spelling of 1991086 in words is "one million, nine hundred ninety-one thousand, eighty-six".