405398321 has 2 divisors, whose sum is σ = 405398322. Its totient is φ = 405398320.

The previous prime is 405398267. The next prime is 405398353. The reversal of 405398321 is 123893504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 304677025 + 100721296 = 17455^2 + 10036^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-405398321 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (405398821) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202699160 + 202699161.

It is an arithmetic number, because the mean of its divisors is an integer number (202699161).

Almost surely, 2^405398321 is an apocalyptic number.

It is an amenable number.

405398321 is a deficient number, since it is larger than the sum of its proper divisors (1).

405398321 is an equidigital number, since it uses as much as digits as its factorization.

405398321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25920, while the sum is 35.

The square root of 405398321 is about 20134.5057302135. The cubic root of 405398321 is about 740.1060969134.

The spelling of 405398321 in words is "four hundred five million, three hundred ninety-eight thousand, three hundred twenty-one".