320878399 has 2 divisors, whose sum is σ = 320878400. Its totient is φ = 320878398.

The previous prime is 320878391. The next prime is 320878409. The reversal of 320878399 is 993878023.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 320878399 - 2³ = 320878391 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (320878391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 160439199 + 160439200.

It is an arithmetic number, because the mean of its divisors is an integer number (160439200).

Almost surely, 2^320878399 is an apocalyptic number.

320878399 is a deficient number, since it is larger than the sum of its proper divisors (1).

320878399 is an equidigital number, since it uses as much as digits as its factorization.

320878399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 653184, while the sum is 49.

The square root of 320878399 is about 17913.0789927360. The cubic root of 320878399 is about 684.6156573738.

The spelling of 320878399 in words is "three hundred twenty million, eight hundred seventy-eight thousand, three hundred ninety-nine".