21222221023 has 2 divisors, whose sum is σ = 21222221024. Its totient is φ = 21222221022.

The previous prime is 21222221021. The next prime is 21222221029. The reversal of 21222221023 is 32012222212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21222221023 - 2¹ = 21222221021 is a prime.

Together with 21222221021, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21222221021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10611110511 + 10611110512.

It is an arithmetic number, because the mean of its divisors is an integer number (10611110512).

Almost surely, 2^21222221023 is an apocalyptic number.

21222221023 is a deficient number, since it is larger than the sum of its proper divisors (1).

21222221023 is an equidigital number, since it uses as much as digits as its factorization.

21222221023 is an evil number, because the sum of its binary digits is even.

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

Adding to 21222221023 its reverse (32012222212), we get a palindrome (53234443235).

The spelling of 21222221023 in words is "twenty-one billion, two hundred twenty-two million, two hundred twenty-one thousand, twenty-three".