21001220022023 has 4 divisors (see below), whose sum is σ = 21345502317528. Its totient is φ = 20656937726520.

The previous prime is 21001220022019. The next prime is 21001220022089. The reversal of 21001220022023 is 32022002210012.

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 21001220022023 - 2² = 21001220022019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001220021992 and 21001220022010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21001220012023) 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, 172141147661 + ... + 172141147782.

It is an arithmetic number, because the mean of its divisors is an integer number (5336375579382).

Almost surely, 2^{21001220022023} is an apocalyptic number.

21001220022023 is a deficient number, since it is larger than the sum of its proper divisors (344282295505).

21001220022023 is an equidigital number, since it uses as much as digits as its factorization.

21001220022023 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 344282295504.

The product of its (nonzero) digits is 192, while the sum is 17.

Adding to 21001220022023 its reverse (32022002210012), we get a palindrome (53023222232035).

The spelling of 21001220022023 in words is "twenty-one trillion, one billion, two hundred twenty million, twenty-two thousand, twenty-three".