1999811 has 8 divisors (see below), whose sum is σ = 2257200. Its totient is φ = 1755040.

The previous prime is 1999799. The next prime is 1999817. The reversal of 1999811 is 1189991.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1999811 - 2¹⁴ = 1983427 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1999817) by changing a digit.

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, 2816 + ... + 3453.

It is an arithmetic number, because the mean of its divisors is an integer number (282150).

2^1999811 is an apocalyptic number.

1999811 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1999811 is a deficient number, since it is larger than the sum of its proper divisors (257389).

1999811 is a wasteful number, since it uses less digits than its factorization.

1999811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6309.

The product of its digits is 5832, while the sum is 38.

The square root of 1999811 is about 1414.1467392035. The cubic root of 1999811 is about 125.9881361132.

The spelling of 1999811 in words is "one million, nine hundred ninety-nine thousand, eight hundred eleven".