21232021023 has 8 divisors (see below), whose sum is σ = 31454846000. Its totient is φ = 14154680664.

The previous prime is 21232021009. The next prime is 21232021039. The reversal of 21232021023 is 32012023212.

It is not a de Polignac number, because 21232021023 - 2⁴ = 21232021007 is a prime.

It is a super-2 number, since 2×21232021023² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21232020987 and 21232021005.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232021043) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 393185548 + ... + 393185601.

It is an arithmetic number, because the mean of its divisors is an integer number (3931855750).

Almost surely, 2^21232021023 is an apocalyptic number.

21232021023 is a deficient number, since it is larger than the sum of its proper divisors (10222824977).

21232021023 is an equidigital number, since it uses as much as digits as its factorization.

21232021023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 786371158 (or 786371152 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

Adding to 21232021023 its reverse (32012023212), we get a palindrome (53244044235).

The spelling of 21232021023 in words is "twenty-one billion, two hundred thirty-two million, twenty-one thousand, twenty-three".