21231121023 has 24 divisors (see below), whose sum is σ = 35061904800. Its totient is φ = 12127325184.

The previous prime is 21231120971. The next prime is 21231121027. The reversal of 21231121023 is 32012113212.

It is not a de Polignac number, because 21231121023 - 2¹⁰ = 21231119999 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21231120987 and 21231121005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21231121027) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99783 + ... + 228951.

It is an arithmetic number, because the mean of its divisors is an integer number (1460912700).

Almost surely, 2^21231121023 is an apocalyptic number.

21231121023 is a deficient number, since it is larger than the sum of its proper divisors (13830783777).

21231121023 is a wasteful number, since it uses less digits than its factorization.

21231121023 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131791 (or 131788 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 21231121023 its reverse (32012113212), we get a palindrome (53243234235).

The spelling of 21231121023 in words is "twenty-one billion, two hundred thirty-one million, one hundred twenty-one thousand, twenty-three".