678181809 has 4 divisors (see below), whose sum is σ = 904242416. Its totient is φ = 452121204.

The previous prime is 678181807. The next prime is 678181831. The reversal of 678181809 is 908181876.

678181809 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 not a de Polignac number, because 678181809 - 2¹ = 678181807 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (678181807) 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, 113030299 + ... + 113030304.

It is an arithmetic number, because the mean of its divisors is an integer number (226060604).

Almost surely, 2^678181809 is an apocalyptic number.

It is an amenable number.

678181809 is a deficient number, since it is larger than the sum of its proper divisors (226060607).

678181809 is a wasteful number, since it uses less digits than its factorization.

678181809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 226060606.

The product of its (nonzero) digits is 193536, while the sum is 48.

The square root of 678181809 is about 26041.9240648613. The cubic root of 678181809 is about 878.5814822943.

The spelling of 678181809 in words is "six hundred seventy-eight million, one hundred eighty-one thousand, eight hundred nine".