21131123011023 has 4 divisors (see below), whose sum is σ = 28174830681368. Its totient is φ = 14087415340680.

The previous prime is 21131123010931. The next prime is 21131123011027. The reversal of 21131123011023 is 32011032113112.

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

It is not a de Polignac number, because 21131123011023 - 2¹⁰ = 21131123009999 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 (21131123011027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3521853835168 + ... + 3521853835173.

It is an arithmetic number, because the mean of its divisors is an integer number (7043707670342).

Almost surely, 2^{21131123011023} is an apocalyptic number.

21131123011023 is a deficient number, since it is larger than the sum of its proper divisors (7043707670345).

21131123011023 is an equidigital number, since it uses as much as digits as its factorization.

21131123011023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7043707670344.

The product of its (nonzero) digits is 216, while the sum is 21.

Adding to 21131123011023 its reverse (32011032113112), we get a palindrome (53142155124135).

The spelling of 21131123011023 in words is "twenty-one trillion, one hundred thirty-one billion, one hundred twenty-three million, eleven thousand, twenty-three".