21201023023 has 4 divisors (see below), whose sum is σ = 22316866360. Its totient is φ = 20085179688.

The previous prime is 21201022981. The next prime is 21201023047. The reversal of 21201023023 is 32032010212.

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

It is a cyclic number.

It is not a de Polignac number, because 21201023023 - 2⁹ = 21201022511 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21201022988 and 21201023006.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21201023923) 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, 557921640 + ... + 557921677.

It is an arithmetic number, because the mean of its divisors is an integer number (5579216590).

Almost surely, 2^21201023023 is an apocalyptic number.

21201023023 is a deficient number, since it is larger than the sum of its proper divisors (1115843337).

21201023023 is a wasteful number, since it uses less digits than its factorization.

21201023023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1115843336.

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21201023023 its reverse (32032010212), we get a palindrome (53233033235).

The spelling of 21201023023 in words is "twenty-one billion, two hundred one million, twenty-three thousand, twenty-three".