5639809 has 4 divisors (see below), whose sum is σ = 6445504. Its totient is φ = 4834116.

The previous prime is 5639797. The next prime is 5639813. The reversal of 5639809 is 9089365.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 9089365 = 5 ⋅1817873.

It is not a de Polignac number, because 5639809 - 2⁹ = 5639297 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (5639839) 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, 402837 + ... + 402850.

It is an arithmetic number, because the mean of its divisors is an integer number (1611376).

Almost surely, 2^5639809 is an apocalyptic number.

It is an amenable number.

5639809 is a deficient number, since it is larger than the sum of its proper divisors (805695).

5639809 is an equidigital number, since it uses as much as digits as its factorization.

5639809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 805694.

The product of its (nonzero) digits is 58320, while the sum is 40.

The square root of 5639809 is about 2374.8282043129. The cubic root of 5639809 is about 178.0005996697. Note that the first 3 decimals are identical.

The spelling of 5639809 in words is "five million, six hundred thirty-nine thousand, eight hundred nine".