20403340423 has 4 divisors (see below), whose sum is σ = 20707867960. Its totient is φ = 20098812888.

The previous prime is 20403340393. The next prime is 20403340487. The reversal of 20403340423 is 32404330402.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20403340423 - 2²⁵ = 20369785991 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 (20403340523) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 152263668 + ... + 152263801.

It is an arithmetic number, because the mean of its divisors is an integer number (5176966990).

Almost surely, 2^20403340423 is an apocalyptic number.

20403340423 is a deficient number, since it is larger than the sum of its proper divisors (304527537).

20403340423 is an equidigital number, since it uses as much as digits as its factorization.

20403340423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 304527536.

The product of its (nonzero) digits is 6912, while the sum is 25.

Adding to 20403340423 its reverse (32404330402), we get a palindrome (52807670825).

The spelling of 20403340423 in words is "twenty billion, four hundred three million, three hundred forty thousand, four hundred twenty-three".