21223021121021 has 8 divisors (see below), whose sum is σ = 21796675822080. Its totient is φ = 20649369553488.

The previous prime is 21223021121009. The next prime is 21223021121053. The reversal of 21223021121021 is 12012112032212.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21223021121021 - 2¹⁸ = 21223020858877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21223021120984 and 21223021121002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21223021121321) 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, 21086900 + ... + 22070418.

It is an arithmetic number, because the mean of its divisors is an integer number (2724584477760).

Almost surely, 2^{21223021121021} is an apocalyptic number.

It is an amenable number.

21223021121021 is a deficient number, since it is larger than the sum of its proper divisors (573654701059).

21223021121021 is an equidigital number, since it uses as much as digits as its factorization.

21223021121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1566763.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21223021121021 its reverse (12012112032212), we get a palindrome (33235133153233).

The spelling of 21223021121021 in words is "twenty-one trillion, two hundred twenty-three billion, twenty-one million, one hundred twenty-one thousand, twenty-one".