1994809 has 4 divisors (see below), whose sum is σ = 2013220. Its totient is φ = 1976400.

The previous prime is 1994807. The next prime is 1994827. The reversal of 1994809 is 9084991.

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

It can be written as a sum of positive squares in 2 ways, for example, as 547600 + 1447209 = 740^2 + 1203^2 .

It is a cyclic number.

It is not a de Polignac number, because 1994809 - 2¹ = 1994807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1994807) 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 3 ways as a sum of consecutive naturals, for example, 9042 + ... + 9259.

It is an arithmetic number, because the mean of its divisors is an integer number (503305).

2^1994809 is an apocalyptic number.

It is an amenable number.

1994809 is a deficient number, since it is larger than the sum of its proper divisors (18411).

1994809 is a wasteful number, since it uses less digits than its factorization.

1994809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18410.

The product of its (nonzero) digits is 23328, while the sum is 40.

The square root of 1994809 is about 1412.3770742971. The cubic root of 1994809 is about 125.8830063770.

The spelling of 1994809 in words is "one million, nine hundred ninety-four thousand, eight hundred nine".