673943209 has 4 divisors (see below), whose sum is σ = 697182660. Its totient is φ = 650703760.

The previous prime is 673943203. The next prime is 673943213. The reversal of 673943209 is 902349376.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 357210000 + 316733209 = 18900^2 + 17797^2 .

It is a cyclic number.

It is not a de Polignac number, because 673943209 - 2³ = 673943201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (673943201) 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, 11619682 + ... + 11619739.

It is an arithmetic number, because the mean of its divisors is an integer number (174295665).

Almost surely, 2^673943209 is an apocalyptic number.

It is an amenable number.

673943209 is a deficient number, since it is larger than the sum of its proper divisors (23239451).

673943209 is a wasteful number, since it uses less digits than its factorization.

673943209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 23239450.

The product of its (nonzero) digits is 244944, while the sum is 43.

The square root of 673943209 is about 25960.4161946607. The cubic root of 673943209 is about 876.7472933664.

The spelling of 673943209 in words is "six hundred seventy-three million, nine hundred forty-three thousand, two hundred nine".