20531443423 has 2 divisors, whose sum is σ = 20531443424. Its totient is φ = 20531443422.

The previous prime is 20531443421. The next prime is 20531443459. The reversal of 20531443423 is 32434413502.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20531443423 - 2¹ = 20531443421 is a prime.

Together with 20531443421, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20531443421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10265721711 + 10265721712.

It is an arithmetic number, because the mean of its divisors is an integer number (10265721712).

Almost surely, 2^20531443423 is an apocalyptic number.

20531443423 is a deficient number, since it is larger than the sum of its proper divisors (1).

20531443423 is an equidigital number, since it uses as much as digits as its factorization.

20531443423 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 34560, while the sum is 31.

Adding to 20531443423 its reverse (32434413502), we get a palindrome (52965856925).

The spelling of 20531443423 in words is "twenty billion, five hundred thirty-one million, four hundred forty-three thousand, four hundred twenty-three".