21002221020223 has 4 divisors (see below), whose sum is σ = 21005143278840. Its totient is φ = 20999298761608.

The previous prime is 21002221020149. The next prime is 21002221020227. The reversal of 21002221020223 is 32202012220012.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21002221020223 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 21002221020223.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21002221020227) 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, 1461118528 + ... + 1461132901.

It is an arithmetic number, because the mean of its divisors is an integer number (5251285819710).

Almost surely, 2^{21002221020223} is an apocalyptic number.

21002221020223 is a deficient number, since it is larger than the sum of its proper divisors (2922258617).

21002221020223 is an equidigital number, since it uses as much as digits as its factorization.

21002221020223 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2922258616.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21002221020223 its reverse (32202012220012), we get a palindrome (53204233240235).

The spelling of 21002221020223 in words is "twenty-one trillion, two billion, two hundred twenty-one million, twenty thousand, two hundred twenty-three".