4040809 has 4 divisors (see below), whose sum is σ = 4045140. Its totient is φ = 4036480.

The previous prime is 4040797. The next prime is 4040833. The reversal of 4040809 is 9080404.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 250000 + 3790809 = 500^2 + 1947^2 .

It is a cyclic number.

It is not a de Polignac number, because 4040809 - 2¹¹ = 4038761 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4040009) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 124 + ... + 2845.

It is an arithmetic number, because the mean of its divisors is an integer number (1011285).

Almost surely, 2^4040809 is an apocalyptic number.

It is an amenable number.

4040809 is a deficient number, since it is larger than the sum of its proper divisors (4331).

4040809 is a wasteful number, since it uses less digits than its factorization.

4040809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4330.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 4040809 is about 2010.1763604221. The cubic root of 4040809 is about 159.2781150995.

The spelling of 4040809 in words is "four million, forty thousand, eight hundred nine".