1999806 has 16 divisors (see below), whose sum is σ = 4051200. Its totient is φ = 658008.

The previous prime is 1999799. The next prime is 1999817. The reversal of 1999806 is 6089991.

It is a congruent number.

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 7 ways as a sum of consecutive naturals, for example, 1636 + ... + 2583.

It is an arithmetic number, because the mean of its divisors is an integer number (253200).

2^1999806 is an apocalyptic number.

1999806 is an abundant number, since it is smaller than the sum of its proper divisors (2051394).

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

1999806 is a wasteful number, since it uses less digits than its factorization.

1999806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4303.

The product of its (nonzero) digits is 34992, while the sum is 42.

The square root of 1999806 is about 1414.1449713519. The cubic root of 1999806 is about 125.9880311130.

The spelling of 1999806 in words is "one million, nine hundred ninety-nine thousand, eight hundred six".