21222122021111 has 16 divisors (see below), whose sum is σ = 23573856158496. Its totient is φ = 19101819880000.

The previous prime is 21222122021069. The next prime is 21222122021161. The reversal of 21222122021111 is 11112022122212.

It is not a de Polignac number, because 21222122021111 - 2³⁴ = 21204942151927 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222122021161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 78798710 + ... + 79067571.

It is an arithmetic number, because the mean of its divisors is an integer number (1473366009906).

Almost surely, 2^{21222122021111} is an apocalyptic number.

21222122021111 is a deficient number, since it is larger than the sum of its proper divisors (2351734137385).

21222122021111 is a wasteful number, since it uses less digits than its factorization.

21222122021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157866415 (or 157866393 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21222122021111 its reverse (11112022122212), we get a palindrome (32334144143323).

The spelling of 21222122021111 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twenty-two million, twenty-one thousand, one hundred eleven".