404020399 has 2 divisors, whose sum is σ = 404020400. Its totient is φ = 404020398.

The previous prime is 404020387. The next prime is 404020451. The reversal of 404020399 is 993020404.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 404020399 - 2⁷ = 404020271 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 404020399.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (404020339) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202010199 + 202010200.

It is an arithmetic number, because the mean of its divisors is an integer number (202010200).

Almost surely, 2^404020399 is an apocalyptic number.

404020399 is a deficient number, since it is larger than the sum of its proper divisors (1).

404020399 is an equidigital number, since it uses as much as digits as its factorization.

404020399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 7776, while the sum is 31.

The square root of 404020399 is about 20100.2586799275. The cubic root of 404020399 is about 739.2666212441.

The spelling of 404020399 in words is "four hundred four million, twenty thousand, three hundred ninety-nine".