42804209 has 4 divisors (see below), whose sum is σ = 48919104. Its totient is φ = 36689316.

The previous prime is 42804161. The next prime is 42804217. The reversal of 42804209 is 90240824.

42804209 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-42804209 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (42804239) 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 in 3 ways as a sum of consecutive naturals, for example, 3057437 + ... + 3057450.

It is an arithmetic number, because the mean of its divisors is an integer number (12229776).

Almost surely, 2^42804209 is an apocalyptic number.

It is an amenable number.

42804209 is a deficient number, since it is larger than the sum of its proper divisors (6114895).

42804209 is an equidigital number, since it uses as much as digits as its factorization.

42804209 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6114894.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 42804209 is about 6542.4925678215. The cubic root of 42804209 is about 349.8072653147.

The spelling of 42804209 in words is "forty-two million, eight hundred four thousand, two hundred nine".