20404396423 has 4 divisors (see below), whose sum is σ = 20410529040. Its totient is φ = 20398263808.

The previous prime is 20404396399. The next prime is 20404396469. The reversal of 20404396423 is 32469340402.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32469340402 = 2 ⋅16234670201.

It is a cyclic number.

It is not a de Polignac number, because 20404396423 - 2⁵ = 20404396391 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20404396123) 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 in 3 ways as a sum of consecutive naturals, for example, 3061315 + ... + 3067972.

It is an arithmetic number, because the mean of its divisors is an integer number (5102632260).

Almost surely, 2^20404396423 is an apocalyptic number.

20404396423 is a deficient number, since it is larger than the sum of its proper divisors (6132617).

20404396423 is an equidigital number, since it uses as much as digits as its factorization.

20404396423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6132616.

The product of its (nonzero) digits is 124416, while the sum is 37.

The spelling of 20404396423 in words is "twenty billion, four hundred four million, three hundred ninety-six thousand, four hundred twenty-three".