21222112110021 has 16 divisors (see below), whose sum is σ = 31446698624320. Its totient is φ = 14145135099120.

The previous prime is 21222112110007. The next prime is 21222112110041. The reversal of 21222112110021 is 12001121122212.

21222112110021 is a `hidden beast` number, since 212 + 221 + 1 + 211 + 0 + 0 + 21 = 666.

It is not a de Polignac number, because 21222112110021 - 2¹⁸ = 21222111847877 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21222112109976 and 21222112110003.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21222112110041) 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, 81524335 + ... + 81784236.

It is an arithmetic number, because the mean of its divisors is an integer number (1965418664020).

Almost surely, 2^{21222112110021} is an apocalyptic number.

It is an amenable number.

21222112110021 is a deficient number, since it is larger than the sum of its proper divisors (10224586514299).

21222112110021 is a wasteful number, since it uses less digits than its factorization.

21222112110021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 163313393 (or 163313387 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21222112110021 its reverse (12001121122212), we get a palindrome (33223233232233).

The spelling of 21222112110021 in words is "twenty-one trillion, two hundred twenty-two billion, one hundred twelve million, one hundred ten thousand, twenty-one".