678244209 has 4 divisors (see below), whose sum is σ = 904325616. Its totient is φ = 452162804.

The previous prime is 678244207. The next prime is 678244213. The reversal of 678244209 is 902442876.

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 not a de Polignac number, because 678244209 - 2¹ = 678244207 is a prime.

It is not an unprimeable number, because it can be changed into a prime (678244201) 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, 113040699 + ... + 113040704.

It is an arithmetic number, because the mean of its divisors is an integer number (226081404).

Almost surely, 2^678244209 is an apocalyptic number.

It is an amenable number.

678244209 is a deficient number, since it is larger than the sum of its proper divisors (226081407).

678244209 is a wasteful number, since it uses less digits than its factorization.

678244209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 226081406.

The product of its (nonzero) digits is 193536, while the sum is 42.

The square root of 678244209 is about 26043.1221054619. The cubic root of 678244209 is about 878.6084277743.

The spelling of 678244209 in words is "six hundred seventy-eight million, two hundred forty-four thousand, two hundred nine".