20131123423431 has 16 divisors (see below), whose sum is σ = 26932344937344. Its totient is φ = 13375336519584.

The previous prime is 20131123423343. The next prime is 20131123423441. The reversal of 20131123423431 is 13432432113102.

It is not a de Polignac number, because 20131123423431 - 2¹⁸ = 20131123161287 is a prime.

It is a super-2 number, since 2×20131123423431² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20131123423441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5900161 + ... + 8664533.

It is an arithmetic number, because the mean of its divisors is an integer number (1683271558584).

Almost surely, 2^{20131123423431} is an apocalyptic number.

20131123423431 is a deficient number, since it is larger than the sum of its proper divisors (6801221513913).

20131123423431 is a wasteful number, since it uses less digits than its factorization.

20131123423431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2772590.

The product of its (nonzero) digits is 10368, while the sum is 30.

Adding to 20131123423431 its reverse (13432432113102), we get a palindrome (33563555536533).

The spelling of 20131123423431 in words is "twenty trillion, one hundred thirty-one billion, one hundred twenty-three million, four hundred twenty-three thousand, four hundred thirty-one".