404203391 has 2 divisors, whose sum is σ = 404203392. Its totient is φ = 404203390.

The previous prime is 404203381. The next prime is 404203453. The reversal of 404203391 is 193302404.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 404203391 - 2¹⁰ = 404202367 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 404203391.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (404203361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202101695 + 202101696.

It is an arithmetic number, because the mean of its divisors is an integer number (202101696).

Almost surely, 2^404203391 is an apocalyptic number.

404203391 is a deficient number, since it is larger than the sum of its proper divisors (1).

404203391 is an equidigital number, since it uses as much as digits as its factorization.

404203391 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 26.

The square root of 404203391 is about 20104.8101458333. The cubic root of 404203391 is about 739.3782158229.

Adding to 404203391 its reverse (193302404), we get a palindrome (597505795).

The spelling of 404203391 in words is "four hundred four million, two hundred three thousand, three hundred ninety-one".