20404396399 has 2 divisors, whose sum is σ = 20404396400. Its totient is φ = 20404396398.

The previous prime is 20404396391. The next prime is 20404396469. The reversal of 20404396399 is 99369340402.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20404396399 - 2³ = 20404396391 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20404396391) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10202198199 + 10202198200.

It is an arithmetic number, because the mean of its divisors is an integer number (10202198200).

Almost surely, 2^20404396399 is an apocalyptic number.

20404396399 is a deficient number, since it is larger than the sum of its proper divisors (1).

20404396399 is an equidigital number, since it uses as much as digits as its factorization.

20404396399 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1259712, while the sum is 49.

The spelling of 20404396399 in words is "twenty billion, four hundred four million, three hundred ninety-six thousand, three hundred ninety-nine".