2009806 has 4 divisors (see below), whose sum is σ = 3014712. Its totient is φ = 1004902.

The previous prime is 2009789. The next prime is 2009807. The reversal of 2009806 is 6089002.

It is a semiprime because it is the product of two primes.

It is a super-3 number, since 3×2009806³ = 24354749666213335848, which contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2009807) by changing a digit.

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 as a sum of consecutive naturals, namely, 502450 + ... + 502453.

It is an arithmetic number, because the mean of its divisors is an integer number (753678).

2^2009806 is an apocalyptic number.

2009806 is a deficient number, since it is larger than the sum of its proper divisors (1004906).

2009806 is a wasteful number, since it uses less digits than its factorization.

2009806 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1004905.

The product of its (nonzero) digits is 864, while the sum is 25.

The square root of 2009806 is about 1417.6762677001. The cubic root of 2009806 is about 126.1976824695.

The spelling of 2009806 in words is "two million, nine thousand, eight hundred six".